Set Appliance State:
Set Multimeter to DC Volts 
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
Test 1:
Measure the DC voltage between the small soldered point marked "5V" just to the bottom left of connector X20 and a suitable earth.
Expect approximately 5 vdc.
Test 2:
Measure the DC voltage between terminals 8 and 9 on the incoming mains terminal strip.
Expect approximately 22 vdc.
Measure the DC voltage between the small soldered point marked "5V" just to the bottom left of connector X20 and a suitable earth.
Expect approximately 5 vdc.
Test 2:
Measure the DC voltage between terminals 8 and 9 on the incoming mains terminal strip.
Expect approximately 22 vdc.
Isolate as per TOPs P4
and refit as necessary