Emerson Liebert NX 50 and 60 Hz - Manual (Page 120)

Options—For Assembly Inside the UPS Cabinet
108
9.1.6 Battery Ground Fault Detection
In addition to any residual current device mounted externally and upstream the UPS or when
optional isolation transformers are fitted to the UPS, an optional residual battery current device can
be fitted to detect leakage current from the battery into the PE (Protective Earth) Residual current
range monitored: 30~3000mA.
Power supply voltage for the set: AC230V (L-N);
When a battery ground fault is detected, an alarm will appear on the UPS display panel.
An additional Dry contact fault Alarm signal is available for remote monitoring:
The Battery ground fault detection set contains one CT (current transformer) and one DC sensitive
residual current monitor. The connection of this set for UPS is illustrated as follows.
Figure 74 Battery ground fault detection set connections
The Battery Ground Fault Detection Set is assembled within the UPS cabinet.
Table 27 Dry contact fault alarm signal is available for remote monitoring
Terminal Name Definition
21 Common
Battery Ground Fault Detection – can be
programmed as Alarm or Pre-Alarm
22 NC
24 NO
BCB or
Contactor
Battery
Batt-N
Socket Output
Phase
Output
Neutral
Current
Transformer
W1-A358
X
Monitor Board
-U2
UPS
IN DRY-X3
+12V
BtG
Battery Ground
Fault Detection
Resys B470
(AC230)
11
14
A1
A2
K1 K2 I2 I2
4
2