GB2374741A

GB2374741A - Door operator control

Info

Publication number: GB2374741A
Application number: GB0217004A
Authority: GB
Inventors: Terence Crimmins
Original assignee: Chamberlain Group Inc
Current assignee: Chamberlain Group Inc
Priority date: 1998-04-21
Filing date: 1999-04-20
Publication date: 2002-10-23
Anticipated expiration: 2019-04-20
Also published as: GB2372866B; GB0217004D0; GB0213634D0; GB2372866A; GB2374741B

Abstract

Switches for operating open, close, stop and learn functions are located on the controller to facilitate installation, maintenance and programming by a service provider at the door operator.

Description

237474 1

CONTROLLER FOR A DOOR OPEN TOR

Background of the Invention

This invention relates to a controller for controlling a commercial door operator or barrier operator, and more particularly to a controller for 5 controlling the motor, interface, safety systems and other functions or a commercial door or barrier operator Commercial door operators, depending on the voltage requirements necessitated by the size and weight of the door-or barrier to be moved, use single phase and three 10 phase induction motors to move the door. Some door operator applications require use of a DC motor, which is somewhat easier to start. Creating enough starting torque and being able to select the direction of rotation of an induction motor is an important function of a door 15 operator.

In a single phase induction motor, the rotor is of the squirrel cage type. The stator has a main winding which produces a pulsating field. At standstill, the

pulsating field cannot produce rotor currents that will

20 act on the air-gap flux to produce rotor torque.

However, once the rotor is turning, it produces a cross flux at right angles with the main field and produces a

rotating field comparable to that produced by the stator

of a two-phase motor.

25 To start a single phase motor, a starting coil is used In a capacitive motor, the starting winding is connected to the Supply through a capacitor. This results in the starting winding current leading the applied voltage The motor then has winding currents at 30 standstill that are nearly 90 degrees apart in time and space, thus producing high starting torque and high power factor

- 2 A three phase motor has three coils, so applying current to each coil always produces current which leads the applied voltage, resulting in sufficient starting torque to start the motor 5 Traditionally, because of the high current required for operating the motor used to drive a commercial door, co. ercia1 door operators employed an electromechanical control package The electromechanical control package typically used relays for logic functions and contactors 10 for motor control Contactors are essentially relays that can switch large currents. While electromechanical control packages are considered reliable in the field and

cost effective, they have limited versatility Their logic functions are hard wired at the factory and not 15 field programmable, so customers cannot change the

configuration of their door operators after acquiring them. Also, electromechanical control packages do not readily accommodate additional features, although additional features, such as delay on reverse and start 20 coil control can be provided via costly add-on modules Other features, such as an RS-232 interface, RPM system and maximum run timer, are not possible at all.

To overcome some of the lam; cations of the electromechanical control packages, some commercial door 25 operators employ a solid state controller. The solid state controller includes microelectronics for controlling some of the logic functions and power control electronics for controlling the motor The controller, or logic control device, is typically built onto z 30 printed circuit board which is usually located within the electronic control box at the head of the operator Specialized programmable functions, such as storing and responding to t arsmitter codes (if the operator has a radio control feature) and failsafe operation features

) - 3 (such as for a fire door), a-e usually handled on c separate programmable logic board, which also sits in the electronic control box. The solid state logic control device includes DIP switches for selecting control 5 options, such as the B2, C2, D1 and E2 options described below. Other functions may be provided by software programs in an onboard nonvolatile memory and run by an Inboard microprocessor.

One particular prior art solid state logic control

10 device employs five triacs in lieu of contactors for cons-rolling the motor. Four of the triacs are used in an H-bridge circuit to steer current in order to control the direction of rotation (the motor start coil of a single phase motor), one pair for the forward direction and the 15 other pair for the reverse direction; the fifth triac is used to control the motor main coil. Since a triac is a solid state device and, in theory, should have no maximum useful switch cycles, a triac should be more reliable than a contactor. A contactor, or relay, will fail 20 eventually due to mechanical fatigue or erosion of the electrical contacts or some other mechanical part anywhere from 50,000 to 500,000 cycles. While the five triac solution provides cost reductions over the contactors and relays used in the electromechanical 25 control package, the triacs have proven to be less reliable than the contactors.

Triacs, while solid state, are susceptible to voltage spikes across the power line, or local dV/dt tolerance. In the prior art motor control in which the

30 two pairs of triacs were joined together on either side of the motor start coil, one triac or each pair was connected to AC neutral, the other side of the triac pair was connected to AC hot. This enabled the triacs to reverse the polarity of the motor start coil, thus

- 4 reversing the rotational direction of the motor However, power line spikes, high dv/dt, can cause the triacs to switch on, when they should not. If a pair of triacs turns on simultaneously, this causes a dead short 5 between AC neutral and AC hot through the Iliac pair, burning out the triacs or the printed circuit boa-d traces. In addition to the effect of power line spikes on the triacs, the motor itself can sometimes produce enough 10 noise to turn on the triacs in the H-bridge circuit.

Many of the traditional techniques for minimizing the effect of power line spikes have been tried: capacitors across the triacs, MOVs and snubber networks.

Unfortunately, none of the traditional techniques have 15 worked Many commercial door operators are equipped with single phase capacitor start motors, which include a -

start coil and a main coil. The motor is activated by supplying AC current to the start coil and the main coil 20 As described above, the start coil is used to give the motor its initial rotational direction (forward or reverse) and high starting torque characteristics.

During operation, the motor accelerates to approximately eighty percent of its synchronous speed, at which point a 25 mechanical governor opens the start coil circuit by opening an inline switch. After the motor reaches eighty percent (or such other manufacturer specified percentage of the motors maximum rated speed), the start coil is no longer needed. Indeed, if the start coil is left 30 energized, copper losses would cause the motor to overheat. The mechanical governors used in the single phase motors generally consist of a centrifugal governor and switch assembly. While relatively inexpensive; they are

unreliable. The most common malfunctions of the centrifugal governor and switch assembly are seizing on the governor and switch contact failure Once the mechanical governor fails, the start coil cannot be 5 activated on start up, resulting in no motor rotation Some motor manufacturers (and third party suppliers) offer built-in or add-on electronic modules ' or shutting off the start coil These electronic packages are more expensive than the mechanical governors. For example, 10 some motor controllers rely on a set time delay and no RPM Measurement. In such systems, the start coil is energized for a predetermined time, say half a second, and then released. This approximation works as long as the motor will start and continue to rotate in the 15 desired direction given temperature variations, load variations, starting torque requirements for the application. Commercial door applications generally require RPM measurements to adequately control the start coil. 20 To assist in the maintenance of the commercial door operator, many include a cycle counter. A cycle counter increments a mechanical odometer type counter every time the commercial door cycles open or closed. The odometer is then read, for example, during routine servicing of 25 the operator and the door. If the odometer reading is beyond a certain cycle count, the service provider may elect to replace certain hardware or even the entire operator. In operators having an electromechanical control package, the cycle counter is an add-on unit, 30 which increases the cost of the operator. The cycle counter is also typically mounted within the operator head, requiring the service provider to climb a ladder to read it. Also, the cycle counter provides no warning when cycle threshold counts are reached

Most commercial garage door openers include G wall mounted switch for allowing a user to command the ooen/close/stop functions. When the service provider installs the operator or performs maintenance, it is 5 often inconvenient for him to leave the operator and climb down the ladder to operate the open/close/stop switches on the wall.

There is a need for a controller for controlling a commercial door or barrier operator which is not 10 sensitive to power line spiking, dV/dt, or motor noise.

There is also a need for a controller which is robust and inexpensive. There is a further need for a controller which includes an integrated start coil control, eliminating the requirement for a mechanical governor.

15 There is a need for a motor start control circuit which causes the motor to start and continue to rotate in the desired direction given temperature variations, load variations, starting torque requirements for the application. There is a need for a controller which can 20 support additional functions, such as an integrated cycle counter and open/close/sto switches for adjustments.

Summarv of the Invention To achieve the foregoing and other objects, a controller for controlling a motor and other functions in 25 a commercial door or barrier operator according to the invention is described. The controller eliminates dV/dt sensitivity by eliminating the four triacs in the current steering H-bridge circuit for selecting the direction of rotation (e.g. in a single phase motor for activating the 30 start coil) and replacing them with two dual-pole-dual-

throw (SPAT) relays. The fifth triac is used to control the current to the main (or third) coil of the motor.

While the fifth trial may still be turned on by power

line spikes and motor noise, since it is in series with the large impedance of the motor, it is not susceptible to shorting out.

In this application, the use of DPDT relays is not a 5 problem because of their apparent shorter life. In the single phase motor maid switching and hold current flows through the motor main coil so the start coil is energized for only about one half of a second per operation cycle. After the motor reaches a predetermined 10 percentage (e.g., 801) of its manufacturer's defined maximum synchronous speed, the start coil is released and the main coil and its switching means provide the brunt of the electrical work. And, since DPDT relays are less costly than triacs, using a combination of two DPDT 15 relays to control the start coil current (or control direction of rotation in a three phase motor) and a triac to control the main (third) motor coil provides a very robust and inexpensive system.

An integrated motor start control for a barrier 20 operator according to the invention includes a speed governor integrated into the controller. The integrated speed governor has an RPM sensor for detecting the speed of the operator's limit shaft coupled to software run by the microprocessor. Motor output speed depends on 25 manufacturer, manufacturer's lot, temperature of operation and environment, load and starting requirements. Measuring the output of the motor itself, as discussed above, can be costly especially if an RPM sensor is built into the motor. Measuring the RPM of the 30 operators limit shaft is an easier and more effective means of determining motor output.

The limit shaft is used to set the door open and close limits of travel. It is coupled to the motor output shaft but rotates at a reduced percentage of the

- 8 motor output shaft using gear reduction. When the motor is installed on the operator, the limit shaft speed can be measured and the predetermined percentage calculated and stored in the onboard memory. The microprocessor or 5 other digital control device, such as an ASIC, gate array or programmable logic device, is programmed to open a switch when the limit shaft RPM reaches a fixed percentage, say, 80 of the measured maximum limit shaft speed A simple switch coupled with the programmable 10 feature provides greater reliability, convenience and lower cost than a centrifugal switch. Many different types of RPM sensors may be used. A preferred RPM sensor consists of an interrupter cup and interrupter module.

An onboard cycle counter enables the installer or 15 service provider to program a desired cycle count into the onboard memory. When the microprocessor detects that the number of cycles (such as the number of tomes the microprocessor opened the start coil switch) reaches the predetermined amount, a warning light is activated. The 20 warning light can be a light emitting diode (LED) mounted on the head unit and/or an LED mounted on the wall control unit. In this way, the customer is alerted to-

the fact that the door has cycled the predetermined namer or cycles and that service should be provided.

25 Alternatively, a display can be mounted on the head unit and/or on the wall unit. A display may show the actual count value stored in the memory. Additionally, i. the operator has an RS-232 port, the value of the cycle counter can be interrogated and inspected at any time at 30 a remote location and the value displayed on, for example, a computer display. For example, the cycle count can be checked when a part of the operator or door is being replaced to gain knowledge of the field life of

the item.

9 - To facilitate installation, adjusting and testing o' the commercial door operator, onboard ooen/close/stop switches are provided on the logic control device. This enables the service provider to open, close or stop S operation of the door from the operator, without having to climb up and down the ladder or walk over to the wall switch. Additionally, the onboard open/close/stop switches may be used to program in various functions to the operator.

10 _ Brief Description of the Drawings

Figure 1 is a perspective view of a door operator mounted to a rail/chain driven door; Figures 2A and 2B are perspective views of a door operator mounted to a jackshaft driven door; 15 Figures 3A, 3B, 3C and 3D are exterior views of an electrical box of the door operator of Figure 1; Figure 4 is a block diagram of a door operator including a logic control device according to the invention; 20 Figure 5 is a schematic of a control circuit for a commercial door operator motor according to the invention;. Figure 6A is a schematic showing some of the electrical connections among the elements shown in Figure 1: Figure 6B shows a motor connection for a 115V single phase motor; Figure 7 is a flow chart showing One motor start procedure;. Figure 8 is a flow chart showing the programming of 30 the cycle counter; Figure 9 is a flow chart showing operation of the cycle counter;

Figure 10 is a flow chart showing prop arming of the RPM sensor; and Figure ll is a detailed schematic showing the electrical connections among the elements of the logic 5 control device of Figure 4 Detailed Description or the Preferred -.=hodiments

Referring now to the drawings and especially to Figure 1, a door or barrier operator enrooting one present invention is shown and generally identified by 10 reference numeral 100. The door operator 100 is located at an end of the rail 02 for moving a door 104. Figure 2A shows a wall mounted operator '00 driving a jackshaft type door. Figure 2B shows the operator 100 mounted to the door housing 106. Each door operator 100 includes a 15 motor 14 and electronics box 10, where the controller is located. Figures 3A, 3B, 3C and 3D are side views of portions of operator 100 Electronics box 10 houses the controller 20, AC transformer 18, overload protection 12 20 and the limit shaft assembly with limit shaft switches 11. A schematic layout of electronics box 10 of commercial door operator 100 is shown in Figure 4.

Terminal connections for controller 10 are shown in 25 Figures 6A and 6B. Electronics box 10 houses a motor 14, solenoid brake 16, AC transformer 18, overload 12, limit switch/shaft assembly 22, RPM sensor assembly 24 and controller 20. Overload protection 12 includes an inline thermal circuit breaker. Brake/solenoid 16 is inline 30 with the main winding of the motor. AC transformer 18 is used to provide secondary connections. Preferably, it will provide primary voltages of 120 VAC, 240 VAC, 480 - vAC or 600 vAC, wick a secondary voltage range or 2 -vAC

RM5, minimum of 20 volt-zmperes and maximum Of 100 volt-

amperes at a frequency of 50/60 Hz.

Logic control device 20 includes processor 32 which controls operation of all the electronic functions on the 5 control device. A Zilog brand microprocessor with 8K of onboard ROM (Z86E43) provides added programming functionality. While the Zilog microprocessor includes some outboard memory, preferably an additional wEPROM memory chip (not shown) is used to store various 10 programmable function values and data.

_ Two C-form relays are used to select the direction of rotation for the motor (up or down; open or close). A single triac is used to operate the motors main coil.

This puts non-solid state components at the critical 15 point of the Hbridge, eliminating quality problems with the prior art five triac system. Directional relays 36

and 37 activate the start coil to set the rotational direction of motor i4 (up/down or open/close).

Preferably two C form relays (DPDT) are used to switch 20 polarity or phase or the motor start coil 53. The preferred manufacturer is PUB, part number T92. Triac 38 activates the main coil of motor 14 by allowing main coil current to low. Preferably triac 38 includes a triac coupled with or optoisolation triac, which is used to 25 provide high current switching capability in line with the main motor winding. Connection of single phase 115 volt and single/three phase 230 volts is done directly on high voltage terminal 39. For higher voltage or higher horsepower motors, the secondary of the transformer 18 30 will be connected to high voltage terminal 39.

Controller 20 will have the option of interfacing directly with size 0 and 00 contactors for operators at higher voltages Contactors (not shown) would then be

- 12 used to handle the high voltage switching end be controlled by relays 36, 37 and triac 38 DC power supply 35 includes two separate DC power supplies. A 5 volt supply furnishes 5 volt potential to 5 controller 20 and a 24 volt power supply provides 24 volt potential Lo service the relay coil drive. Local switches are provided for open/close/stop to enable the installer or service provider to make adjustments directly at the electrical box and for programming the 10 operator. Switches 40 includes a four pole DIP switch used for setting modes and programming the operator.

Switch 40 also includes four momentary switches for radio learn, open, close and stop functions. These functions can be used by a service provider during installation, 15 testing and maintenance. Indicator panel 33 includes LEDs for indicating, for example, when the cycle counter has counted a predetermined number of cycles. Terminal strip 34 provides for connection to other boards, sensors and power supply connections in the commercial door 20 operator.

Limit switch assembly 22 provides for setting of the open (or up) and close (or down) limits of travel of the door. The RPM sensor 4 in combination with the microprocessor 32 is used to eli...inate the centrifugal 25 switch. The RPM sensor and microprocessor control current to the start coil and permits more accurate control of start coil cutoff. RPM sensor 34 measures the rotation of the limit shaft. Additional connectors may be provided for interfacing with accessory boards, such 30 as a self-monitoring IN system and a warning signal board (not shown).

A control circuit for controlling operation of a single phase motor 14 is shown in Figure 5. Triac 38 is shown in series with main coil 51 of motor 14 between AC

- 13 hot and AC neutral When triac 38 is switched on, it supplies AC current to the main coil 51 of the motor 14.

When the user selects open (up) or close (down) from a wall switch (not shown), either directional relay 36 (up) 5 or relay 37 (down) is activated to supply AC current to the start coil 53. With either relay 36 or 37 in the circuit, start coil 53 is -n series with main coil S1.

When switch assembly 54 detects that motor 14 has reached a predetermined percentage of its maximum rotational lO speed, it opens taking start coil 53 out of the circuit, leaving only main coil 51 to drive the motor 14. Switch assembly 54 can be a mechanical switch, such as a centrifugal switch assembly or an RPM sensor assembly.

The inserts in Figure 6A show 115V and 208/230V single 15 phase motor corrections.

If switch assembly S4 comprises the preferred RPM sensor assembly, a photointerrupter measures limit shaft speed (reduced value of motor output shaft speed) and applies the value to microprocessor 32. Microprocessor 20 32 compares the detected limit shaft speed with a stored value, Sm. the maximum shaft value in nonvolatile memory.

When the detected limit shaft speed reaches, for example, 80t of Sm. microprocessor 32 shuts off the directional relay 36 or 37, disengaging the start coil 53. The main 25 coil 51 continues to operate the motor 14 until the microprocessor shuts off AC power to the main coil.

Figure 6B shows the connections for a 230 VAC three phase motor in which triac 38 applies current to coil T3 of motor 14 at connection Elf, and relays 36 and 37 are 30 connected at corrections El6 and E17 to provide current and direction of rotation to coils T1 and T2 of motor 1.

Inserts in Figure 6B show 208/230 VAC and 60 VAC three phase motor connections.

Referring to Figure ll, microprocessor 832 is shown as a Zilog brand model Z867 3 Additional nonvolatile programmable memory is provided by EEPROM 850.

Connectors P1 and P7 provide a connection for optional 5 contactors in the event a higher voltage door operator is required. For the small voltage systems using the smaller motors with '15V or 208/230 7 supplies, con-cl is provided by the triac/DPDT relay control. In response to a user command, microprocessor & 2 sends an enable 10 command to optoisolator triac 838 via pin P01 which enables triac 840. In response to a directional input from the user, microprocessor 832 enables either relay 836 or 837 via pins P00 and P35. RPM input from the off board RPM sensor is provided at terminal 803 to 15 microprocessor 832 Similarly off board limit switch information is provided to microprocessor 832 via terminal 802. Onboard switches S3, S4 and S2 provide open, close and stop functions with corresponding LEDs.

Switch panel S1 contains 4 DIP switches for setting the 20 various operating modes described herein.

A flowchart of the motor start procedure is shown in Figure 7. Microprocessor 32 controls current to the motor start and run windings. After the motor is up to speed, the start winding is turned off and the run (main) 25 winding left on. As a safety precaution, if the motor does not achieve a predetermined speed after a set time, the motor is turned off by interrupting current to the main coil and to the start coil. Referring to Figure 7, the microprocessor responds to a command from the open or 30 close switch and turns on the motor's Run (or main) winding by activating the triac in Step 01. In Step - 402, the routine determines the door's travel state. In Step ^03 it checks for Up-Travel state. If the answer is yes, it turns on the motor start winding, by acti -=ting

- 15 the Up relay in Step 405. If the answer is no, in Step 0 it checks for Down-Travel state. If the answer to either is yes, it turns on the motor start winding by activating the Down relay in Step 406. If the answer is 5 no, it sets the error flag in Step 407, then in Step 08 shuts off the Start relay and the Triac, thereby turning c'f the motor and exits.

At Step 409 it checks for motor REM. If the RPM is UP to speed or the default timer has expired in Step 4 0, 10 it shuts off the Start relay only and allows the motor to continue to run in Step 412, then exits. If the RPM is not up to speed or the timer has not expired, it checks for maximum time in Step 411. If the answer is no, it branches back to Step 09. If the answer is yes, it 15 branches to Step 408.

A logic control device for use in a commercial door operator must be capable of operating at temperatures from - 0 degrees Celsius to +65 degrees Celsius. The logic control device must operate with ll5V, 208V, 240v, 20 380V, 460V and 575V single and three phase (SO and 60 Hz) door operators. Although, in general, higher voltage operators (460V and 575V) may require contactors in lieu of relays due to the extremely high currents. The logic control device must endure 250,000 cycles without a major 25 failure.

Integrated Motor Start Coil Control To properly control the start coil, the motor RPM must be measured. At 801 (or some predetermined percentage'depending on the particular motor chosen for 30 the operator) of the motors rated RPM, the start coil is released and the motor continues to turn in the same direction, activated by the main coil.

Many motor controllers measure RPM at the main rotor shaft. This is generally cumbersome and requires

- 16 invading the motor itself For RPM measurement, measuring the limit shaft speed of the door operator provides several advantages The limit shaft assembly is used to maintain the proper relationship between the door 5 position and the operator control state. It is a separate shaft and not part of the motor. The limit shafts RPM is directly refaced co the motor shafts REM, but reduced. The amount of RPM reduction depends on the operator type and must be calibrated for each operator 10 and when the motor is replaced. In order to measure the limit shaft's RPM, an interrupter cup and photointerrupter module are used. Alternatively, a Hall effect sensor and a ring magnet or one of the numerous available methods of measuring shaft revolution speed may 15 be used.

There is generally no fixed relationship between the licit shaft revolution speed and that of the motor; the relationship varies from motor to motor, even if the motors are the same type and rating. Since limit shaft 20 speed is used to predict motor shaft speed, it is critical to obtain the relationship for each door operator. Given unit differences, each unit must be calibrated when produced and whenever a motor is replaced. Calibration includes the following steps.

25 First, the door operator is placed in the factory test mode. Then run the operator without a load (no door) and measure the limit shaft RPM after two seconds (Sm).

Store Sm in non-volatile memory as a representation o' a full speed motor. Compute 80\ of Sm and use this as the 30 cutoff value o' the limit shaft speed to release the start coil.

Further details of the-RPM programming process are shown in Figure 10, the Motor REP Learn Process. When the door operator is running in a stable acor opening and

door closing manner, the learn button is pressed, Step 701, to put the operator in the RPM sensing mode.

Maximum learn time is limited to lS seconds. In Step 702, the routine checks to see if the 15 second timer is 5 active. If the 15 second timer is not active, Step 703, the routine activates the timer. Then the routine checks if the door is in the Up-Travel state, Step 704 IF not, the routinechecks if the door operator is in the Down-

Travel state, Step AGE. If it is Rio-, the Routine 10 returns to Step 701. If the answer is yes to either of Steps 704 or 705 is yes, the routine branches to Step 706 where it gets the count of the number of RPM pulses within the RPM count interval. In Step 707 the routine checks if the RPM count is greater than the previous 15 count. If yes, it updates the count to the new RPM count in Step 708. If no, it checks for the learn button still pressed at Step 70g. If the learn button is not pressed, the routine saves the RPM count in memory at Step 711 and exits If the learn button is still pressed, the routine 20 checks the 15 second timer in Step 710. If the 15 second timer is still active indicating that less than 15 seconds have elapsed, the routine branches to Step 704.

If the 15 second timer is not active indicating it has timed out the routine saves the RPM count in memory at 25 Step 711.

Programmable Integrated Cycle Counter Cycle count information may be retrieved in many different ways. The simplest method is to turn on an LED or other light when the cycle counter reaches the preset 30 limit. Alternatively, cycle count data can be downloaded or interrogated through an RS-232 link having an RS-232 port connected to microprocessor 32 on controller 20.

A diagnostic LED may be located both on the logic control device and the wall unit, next to the three

button controls (o?en/close/stop). The diagnostic LEDs flash at both the controller in the head unit and the wall unit when the cycle counter reaches the preprogrammed cycle count. The preprogrammed cycle count 5 may be stored in the controller's nonvolatile memory at installation by the service provider using DIP switches or push button inputs. Each time the door operator causes the door to open or close, microprocessor 32 increments a counter which is then compared with the 10 preprogrammed cycle count. When the microprocessor detects a match, it enables the LED indicators. Prior to LED indication, a service provider can download the stored cycle count from the microprocessor through the RS-232 port to obtain information on the number of cycles 15 the operator has cycled the door.

The RS-232 link can be built directly onto the logic control device or Implemented as an alternate, add-on board, which plugs into one of the available option slots on the logic control device: With the add-on board, the 20 microprocessor can be queried and output the exact cycle count. The cycle count can be obtained by a computer connected to the RS-232 port, or a self-contained monitoring module with RS-232 interface and a display for displaying the current count.

25 The predetermined number of cycles for the cycle counter is learned or programmed by programming the microprocessor according to the steps described in Figure 8. Referring to Figure 8, the routine first checks to see if the microprocessor is in any other modes in Step 30 501. The routine checks if the microprocessor is in the diagnostic mode in Step 502. If the answer is no, it branches to Step 531. Cycle count cannot be stored unless the microprocessor is in the diagnostic mode If the answer is yes, it checks for Learn switch depressed

- 19 in C_ep 503 If no, it branches to Step 501. If yes, it increments the counter in Step 504. In step 505 it checks for the mode DIP switch If yes, it branches to step 503 If no, it multiplies the counter by 5000 in 5 Step 506 In Step 507 it stores the cycle count in memory and exits.

The cycle counter increments a court of the number of times the door is opened and closed. The counter is incremented when the door operator is in the up-t a-v-el 10 state after leaving the down limit. Referring to Figure 9, cycle counting begins at Step 601 with the factory initialized settings. In Step 602 the routine checks for a state change. If no, the routine checks for a mode change in Step 603. If no, the routine branches back to 15 Step 601. If yes, in Step 604 the routine checks for the previous set t mer-to-close If yes, the routine stores the new timer-toclose value in Step 606. If no, in Step 605 the routine checks if the previous mode was set mid stop position. If yes, it stores the new midstop 20 position in Step 607. If no, the routine checks for any up or down limits at step 613. If yes, it reads the max-

run-time value at Step 614 and branches back to Step 603.

If no, it cycles back to Step 613.

If the answer to Step 602 is yes, the routine checks 25 for a new uptravel state in Step 608. If no, the routine reads the timer-to-close value in Step 609 then checks if the door has left the down limit and is now in up-travel at Step 615. If the answer to Step 615 is no, it branches to Step 610 If the answer to Step 635 is 30 yes, it reads the cycle counter value in memory at Step 616. Then it increments the cycle counter by one in Step 617 At Step 618 the routine checks i' the cycle counter value equals a stored value. If no, the routine branches

- 20 to Step 602. If yes, the routine issues a cycle count alert at Step 619, then branches back to Step 612.

If the answer to Step 608 is yes, the routine checks if the door is no longer in down travel state at Step 5 610. If the answer is yes, the routine branches to Step 613 If the answer is no, the routine checks if the mode is now being set at Step 611 (DIP switch changes). If the answer is yes, the routine branches to Step 613. I' the answer is no, the routine gets the mid-stop value 10 from memory at Step 612.

_A separate routine is provide for the user-alert trigger sequence resetting procedure At Step 620 the routine checks if the operator is in the diagnostic mode and cycles until it is. When in the diagnostic mode, the 15 unit resets the cycle count and alert signal by storing a zero value in memory and turning off the warning light at Step 621 Open/Close/Stop Typical open/close/stop controls for commercial door 20 operators are in the form of three button wall control stations. Wall controls for electromechanical door operators switch 24 volts AC to the open and close contactor coils, which in turn energize the motor These wall control switches must be large enough (in contact 25 design) to switch up to two amps of AC current through the coils.

A prior art controller uses a three button wall

control station that switches microelectronic logic levels at 5 volts. In this controller, the 30 microprocessor controls the triacs, which in turn control the motor. The microprocessor, which operates at 5 volts, responds to the inputs from the open/close/stop controls, and then applies the appropriate signal to the trial control circuit. Since it takes only about 500

- 2n m crcampS to switch the open/close/stop controls, wiring advantages are gained over the wiring required to switch 2 volts AC. Due to the lower current requirements and relatively low impedance of the wire when compared to the 5 microprocessor input port impedance, lower gauge wiring can be used, or the same gauge required by the electromechanical openers and greater run distances can be achieved As discussed above, many door operator installations 10 are inordinately time consuming because of the need for the operator to travel repeatedly back and forth between the operator and the wall mounted controls. Calibration of the operator for either electromechanical or logic based units, typically involves at a minimum setting up 15 the open, close and auxiliary limits. This calibration takes place at the operator head, activating the unit takes place at the wall. To overcome this deficiency, the controller includes head mounted open, close and stop switches. These switches operate in parallel to the wall 20 mounted switches, but provide added convenience and reduce installation and test time for the service provider. The head mounted switches require small current levels, SOO microamps, and provide only a minimal cost impact on the cost of the operator.

25 In addition to allowing operation of the unit from the electrical box at the head, the head mounted open/close/stop switches are also used to program various features of the unit. Timer to close, cycle counter, and adjustable mid stop can now be easily programmed at the 30 head unit using these buttons as input devices, without the service provider having to climb up and down the ladder to operate the wall mounted open/close/stop Some of the features of the door operator that can be programmed are described below While some features,

- 22 such as modes are programmed by setting DIP switches, others zze programmed by a combination of DIP switch settings and programmable inputs from the open/close/stop switches and an optional learn switch.

5 DIP Switch Settings Mode 1 2 3 4 (l = off, 0 = on) B2 1 1 1 1

B2 Failsafe 1 1 1 0 C2 0 1 1 1

10 C2 Failsafe 1 0 0 0 D1 1 0 1 1

D1 Failsafe ' O 1 0 E2 0 0 1 1

E2 Failsafe O O 1 0 15 T 1 1 0 1

TS O 1 0 1

Set Mid Stop O 1 1 0 Set Timer to close 1 1 0 0 FSTS O 1 0 0

20 Memory clear O O O 1 Diagnostic O O O O Set cycle counter 1 0 0 1 Setting Modes Different modes can be set by adjusting the various 25 DIP switches and the learn mode switch Preferably, the door operator can be operated in the B2, C2, D1, E2, T. and TS operating modes. B2 mode includes momentary contact to open, close and stop, plus wiring for a sensing device to reverse and auxiliary devices to open 30 and close with open override. C2 mode includes momentary contact to open and stop with constant pressure to close, open override plus wiring for sensing device to reverse.

D1 mode includes constant pressure to open and close with wiring for sensing device to stop. E2 mode includes momentary contact to open with override and constant pressure to close. Release of the close button will 5 cause the door to reverse plus wiring for sending device to reverse. T mode includes momentary contact to open, close and stop with open override and timer to close. TS mode includes momentary contact to open, close and stop with open override and timer to close.

10 To set the maximum run timer, the door must be in the_closed position, then the DIP switch settings are adjusted. Press the open switch and allow the door to travel to the full open position. The door functions in the C2 mode during maximum run tamer setting. Change the 15 DIP switch to the desired operating mode (B2, etc.). The maximum run tamer is now set to the door travel time plus ten seconds.

To set the adjustable mid-stop, begin with the door in the closed position. Set the DIP switch to the proper CO position. Press the open button and allow the door to open uninterrupted to the desired mid stop position.

Press the stop switch. Change the DIP switch to the desired operating mode which allows mid stop. To disable mid stop, run the door from the down limit to the up 25 limit without stopping. The mid stop will be disabled and the DIP switch can be placed in the desired operating mode. To set timer to close, begin with the door in the closed position. Set the DIP switch settings to the 30 desired configuration. In this mode the door will not travel. Pressing the open/close/stop control buttons while in this mode sets the timer to close. The -diagnostic light will light every time the electronics receives a valid button closure. The close button will

! _ ?A reset the time to close to its factory set minimum time value of 0 seconds. The open button will increase the time to close value by 5 seconds every time it is depressed Once time is set, change the DIP switch to S the desired operating mode.

When the diagnostic mode is selected in the DI? switch, the diagnostic light will flash two times every second and the door will not function while in this mode If the DIP switch is put in memory clear mode for 30 10 seconds, the unit will light the diagnostic light and the unit_will preset the memory with default values of 90 seconds for maximum run timer, 0 seconds for timer to close, disable mid stop and 0 seconds for cycle counter.

When the DIP switch is in the cycle timer learn 15 mode, the cycle counter warning light will flash the number of tens of thousands of times the unit has cycled followed by a three second pause. For example, if the unit has gone from 10,000 to fig, 999 cycles, the light would flash once followed by a three second delay. To 20 program the cycle counter trip point, the following commands are used. Pressing the close button clears the timer to 0. Every push of the open button increases the cycle counter trip point by 10,000 cycles Once the cycle threshold or trip point is reached the operator 25 will flash the diagnostic light once every two seconds for two seconds until the unit is serviced and the cycle counter is cleared.

While there has been illustrated and described a particular embodiment of the present invention, it will

- 25 be appreciated that numerous changes and modifications will occur to those skilled in the art, and it is intended in the appended claims to cover all those changes and modifications which followed in the true 5 spirit and scope of the present invention i

Claims

AL CLAIMS:

1. A controller for controlling a door operator, located at the door operator, comprising: a digital circuit for processing open, close, stop and other functions of the door operator; a memory storing instructions for operating the door operator and data values pertaining to operation of the door operator; and a plurality of logic controlled switches for providing open, close and stop functions at the controller and for providing programming inputs to the digital circuit effective for enabling a user to service, maintain and test the door operator at the door operator.

2. A controller for controlling a door operator, located at the door operator, comprising: a motor control for controlling a motor for moving the door; a speed sensor external to the motor for sensing a rotational speed of the motor; a decoupler for decoupling a start coil of the motor when an output speed of the motor achieves a predetermined percentage of a maximum rated output speed; a digital circuit for processing open, close, stop and other functions of the door operator; a memory storing instructions for operating the door operator and data values pertaining to operation of the door operator; and a plurality of logic controlled switches for providing open, close and stop functions at the controller and for

l providing programming inputs to the digital circuit effective for enabling a user to service, maintain and test the door operator at the door operator.