Part 12470
Rev. 2 3/25/99
desired test current cannot be reached, transfer output lead to the next higher voltage
(lower current) terminal, and repeat Steps 11 and 12. If test current is still not
reached, transfer output lead to terminal labeled 25A, and repeat Steps 11 and 12 (see
SELECTION OF OUTPUT TERMINAL).
NOTE: Before starting test, allow time for thermal element to cool; or in the case of
magnetic overload relays, for the piston to reset. Incorrect tripping time may
otherwise result.
13. Put ammeter DISPLAY MODE in NORMAL position.
14. Start test by moving OUTPUT MODE Switch to MAINTAIN position.
NOTE: Test current may decrease (fall off) during the test because the resistance or
impedance of the test circuit increases as it heats up. Rotate OUTPUT CONTROL
knob clockwise to keep test current at desired value.
15. When overload relay trips, timer stops and output is de-energized. Timer indicates
total elapsed time of the test in seconds or cycles.
16. Turn test set OFF with POWER ON/OFF Switch.
17. Record test results.
IMPORTANT
In order to obtain accurate tripping times with some types of magnetic overload relays, particularly
those using high viscosity oil, it may be necessary to "preheat" the relay by running rated current
through the relay for a few minutes.
INSTANTANEOUS ELEMENT
1. Set-up CB-832 with:
a. POWER ON/OFF Switch in OFF position.
b. OUTPUT CONTROL knob at minimum, `0' position.
C. OUTPUT MODE Switch in center OFF position.
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