Quadnet Power Supply Unit Installation Manual
20
Further Information
PSU Cable Continuity & Insulation Test Results
After installation of the cable, and termination into all the relevant back-boxes, take cable continuity and
insulation readings. Make sure that all the cables are dressed smoothly and neatly into their back-boxes in
order that they will not be disturbed after the readings are taken.
The commissioning engineer will require these readings, along with correctly marked ‘as-wired’ drawings
and completed configuration sheets, before attending site to commission the system.
CORE
CONTINUITY READING (OHMS)
PSU Data
Power 1
Power 2
+ve to -ve with temp
short circuit applied
-ve to Earth with temp
short circuit applied
+ve to Earth with temp
short circuit applied
A reading of approximately 1 ohm per 100 metres of 1.5 mm
2
cable is expected and any significant
variation from this should be investigated. If the above readings are satisfactorily showing circuit continuity
then you may also take the reading below.
CORE
INSULATION READING (OHMS)
PSU Data
Power 1
Power 2
+ve to -ve
+ve to Screen
-ve to Screen
Screen to Mains Earth
A reading in excess of 1 M ohm is expected and any significant variation from this should be investigated. If
the readings are satisfactory then the loop wiring is largely proven other than for faults such as complete
polarity reversal.
Site Name & Address:
Installation Company:
Testing Engineer:
Signature:
Date:
