Real-Time Clock Calibration On Microprocessor Module - ABB REL 301 Instruction Leaflet

I.L. 40-386.1
17) Turn "ON" the dc power supply and adjust Pot P15 until the Value display reads 0 or FFFF
Hex.
5.4.3

Real-Time Clock Calibration on Microprocessor Module

18) Connect a precision period counter instrument to TP1, on the microprocessor module
and TP7 (common) on the input/filter module.
19) On the microprocessor module, adjust variable capacitor (C6) and read the period of
pulses at TP1. It should be 1.000000 second ( 0.000002).
20) Turn "OFF" the dc power supply.
21) Remove the power leads and external connector.
22) On the microprocessor module, move jumper from position JP6 to JP3 and replace front
panel with six mounting screws.
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