Laboratory manual for the evaluation of non-automatic weighing devices
LG-3.07 Power interruption
Table of contents
Sections 9, 10, 11, 31 and 32 of the Specifications Relating to Non Automatic Weighing Devices (1998)
This test is performed on complete electronic scales and electronic indicators tested separately. This test is to ensure that momentary power failures that can occur during weighing operations will not lead to measurement errors that can not be easily detected. This test also applies to battery-powered devices where the battery is replaceable or rechargeable.
Removable or rechargeable battery must be disconnected; the AZT may be in any status.
- Place a load on the load receiving element and zero the device (by activating the non-automatic zero setting mechanism).
- Place an additional load on the load receiving element and note the registration.
- Unplug the DUT by pulling the plug and, in no less than five (5) and no more than ten (10) seconds, restore the power to the DUT and record the manner the scale returns to operation. Note the registrations.
- Repeat the test, but this time interrupt the power using the power switch of the DUT.
- Repeat the test with a Keyboard or Platter tare entered; repeat the test with preprogrammed tares entered (i.e. tares associated to PLU codes); repeat the test with an "in-bound" weight entered.
Interpretation of results
The DUT is deemed to comply with the requirements if, after interrupting and restoring the power to the DUT, the registration has:
- returned to zero within the prescribed range; or
- returned to an accurate weight value; or
- display a meaningless output or error signal which requires operator intervention; and
- retained the information in memory (In-bound weights and uncompleted transactions shall not be lost during a power failure or when restarting the system).
- Rev. 1 (March 2010)
- AZSM renamed to AZT
- Formatting change
- Date modified: