Bus Power measures
voltage levels on these
two wires (V+ / V-)
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!
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Check your power supply for proper installation
and correct output voltage under load.
Are your trunk/drop cables too long?
Is one or more of your devices drawing too
much current?
For
bus power voltage levels we suggest:
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!
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Check for output devices (like contactors)
powered from the network (they shouldn’t be).
Check for network cables routed too close to
strong sources of interference
Check for aging network power supply with
output ripple increasing over time
For
p-p (noise) levels we suggest:
Bus Power
Examples of transients
25V
13V
Thresholds:
High Voltage Fault
Low Voltage Warning
Low Voltage Fault
High P-P Voltage Fault
High P-P Voltage Warning
25.0V
14.0V
13.0V
10.0V
2.0V
4
BUS
POWER
11
!
If you suspect an intermittent cable or
connector, shake, bend or twist the suspected
cable and/or connector while watching the P-P
measurement for changes (up or down).
