FR2475232A1 - Current measuring and recording meter - includes dry calibrated tape providing permanent record of current drawn by domestic appliance - Google Patents

Abstract

The instrument measures the current drawn by an electrical appliance in one of two ranges: 0-5 amps or 0-25 amps. This measured value is recorded on a dry tape marked with the two ranges. A digital temp. recorder and display is also included in the instrument. The instrument automatically changes from one range to the other at some preset threshold - between 4 and 8 amps. The instrument is protected against current surges, partic. at the changeover from one scale to the other. A delay forbids the temp. to be recorded within a set time of the changeover to avoid accidental erasing of a correct temp. reading. The instrument may be used in checking and repairing domestic electrical equipment - for example a washing machine may draw between 0 and 5 amps during washing, and 0 to 25 amps during heating. This record continues automatically for 2 to 6 minutes after the appliance is switched off.

Description

The oresenrite invention relates to a measuring device intended to facilitate

  liter maintenance of household and related equipment.

  In known devices of this kind, the test benches are generally

  Really constituted by an assembly of various measuring devices such as: meter - voltmeter - ammeter - wattmeter or thermometer, all of these devices providing indications usable only in the measurement

  or their values are read and analyzed at all times by a technician.

  The automated measurement bench according to the invention makes it possible to avoid these

conveniences. It is in fact made up of an electronic circuit automating the operation of an ampermetric tape recorder on dry plot with

  a flow of 20 inch / H providing the following Darameters: time, consumption

o; atio, n deterr..inant state, timing and a digital temperature indicator

memory tale with a measurement possibility from -150 to +750.

The recorder is started automatically as soon as

  the appearance of electrical consumption on the device to be checked.

  The change in measurement range of the 0-5 A or 0-25 A recorder is done automatically as soon as a change of state occurs.

  the device to be controlled, the critical tipping point being adjustable.

  The recorder stops automatically for 2 to 6 minutes, which

  time being adjustable, after stopping the aoDareil to be controlled. In case the ap-

same controlled resumes operation, the recorder also starts

again and that automatically.

This device also allows the "memory" command of an indicator

tenér: digital ature, this command being itself assigned a time-

  pGri - :; ation Protecting it against accidental erasure. This device

tcratisation Allows to avoid the mobilization of a technician in front of the aoDareil to conhrôolr and on the other hand to obtain a strictly Accurate recording of the differ.ts parameters to be checked. Automatic shutdown allowing for

him to avoid waste tape.

  The attached drawings are as follows: Plainchlu lis: block diagram of the electronic automatic control circuit

  of the recorder and the temperature indicator.

Plate 2 /: actual diagram of the electronic circuit for automatic control of

  The temperature recorder and indicator.

  Plate 3/3: representation of the front face of the automated measurement bench

with its different commands.

  As designed, the electronic device firstly includes a consumption detection circuit operating on the principle of the clamp clamp. From this circuit marked (1) in diagram 1/3, we extract a

variable voltage according to the state and the electric moment of the device to be checked.

2 -

  The circuit portions marked (2) in diagram 1/3, allow

  drawing of the voltage detected in (i.) starting the motor of the recorder and on the other hand, on the disappearance of this second voltage, stopping the recorder

  (after an adjustable delay from 2 to 6 minutes).

  In the event that the device to be checked resets again: onctctne-

The process described above takes place again.

The circuit portions marked (3) in diagram 1/3 allow the scale of the recorder to be changed either to 0-5 A scale or to 025 A scale.

Recall that in household appliances using a heating circuit

  fage, for example washing machines or dishwashers, the two determining Yeats are the following: cycle without heating corresponding to the 0-5 A scale and cycle with heating corresponding to the 0-25 A scale.

  The operation of this caliber changer is based on the following principle:

Before: after detection of the electrical consumption of the device to be controlled (1), an adjustable limiter allows the critical change point to be obtained

desired scale (between 4 and 8 A).

  The output voltage of the limiter, amplified, controls the change relay

  scale measurement at the tipping point affected by the aforementioned limiting circuit.

The circuit portions marked (4) in diagram 1/3 are slaved to the scale change of the recorder. The operation is as follows: on the 0-25 A scale the memory contact of the temperature indicator is open, which allows the latter to be analyzed by means of a done temperature control. When returning to scale 0-5 A the memory contact

is closed, and the last temperature indication detected remains displayed.

  To avoid accidental erasure of the display memorized by a brief surin-

  of the device to be controlled, the memory circuit is assigned a time

  rization which authorizes the opening of the holding contact only after several seconds when passing over the 0-25 A scale. The electronic circuit also allows separate use and

"manual" of the measuring devices used in this measuring bench.

  Plate 3/3 is a representation of the front face of the automated measurement bench with its different controls: Mark (1) Amnpermetric recorder Mark (2) Temperature analyzer Mark (3) Light indicator of the recorder's scale in Reference function (4) ON / OFF switch controlling the powering up of the bench

and the device to be checked.

Mark (5) Socket for external temperature probe

Mark (6) Control with marking indicators authorizing automatic operation

matic, stopping or manual operation of the mac ly-eur l. ', -

temperature.

  Reference (7) Control with indicator lights authorizing the l (fiien-rt a,!, Nme-

tick, stopping or permanent scrolling of] '* nreist king.

  Mark (8) Control with marking indicators authorizing the change (ernt.I ', e-liel. (

automatic, manual 5 A scale or manual 2q A scale.

  The actuation of the automated measurement bench is extreme; iîD] it: it is provided with two cables, one with a male plug plus earth to be connected to the mains, the other with a female plug plus earth to be connected to the file s (tc'ur

  of the device to be checked. The digital temperature indicator requires (aprli-

cation or the introduction of a temperature probe on or in the arparei L to be checked. The device, object of the invention, associated with a heath recorder and a digital temperature indicator, therefore allows' in the absence of any natural person to automatically obtain a record orcis.

  corresponding to the operating time and bearing on it undermines all the para-

meters for analyzing any faults in the device to be checked, as well as storing the last positive temperature on cal ibre

0-25 Reached by the device to be checked.

  Particularly interesting applications can be the use of this measurement bench in after-sales services or all services having

  for function the control, the maintenance or the development of electrical devices

  that type of household appliances with time saving and optirm efficiency.

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Claims (5)

R E V E N D I C A T I 0 N S 1 Automated measuring bench including an electronic detection and control circuit allowing the control of the two associated measuring devices   to the set either: an amperometric tape recorder on dry track of cali- 0-5 A / 0-25 A connection and a digital temperature indicator with memory, the assembly being intended for checking and repairing household and similar equipment.   2 measuring bench according to claim (1), characterized in that the start- registration rage is automatically carried out due to consumption of the device to be checked.   3 measuring bench according to claim (1), characterized in that the chan-   0-5 A / 0-25 A measurement scale management of the recorder is performed automatically. and this at any change of state of electrical consumption 0-5 A / 0-25 A of the device to be checked.   4 measuring bench according to claim (1), characterized in that the stopping of the recorder is carried out automatically, from 2 to 6 minutes depending on the setting,   after completely stopping the device to be checked.   Measuring bench according to claim (1), characterized in that the digital temperature indicator is controlled by the 0-25 A amperometric scale of   the recorder for analysis and storage of the last temperature posi- tive reached by the device to be checked on the 0-25 A rating of the recorder. 6 measuring bench according to claim (5), characterized in that the   memory of the digital temperature indicator is protected by a time delay tion of a few seconds against an accidental overcurrent of the device to be checked.