Emerson Liebert NXC User Manual page 57

Communication
Description of the dry contact ports
Silk print Port name
1 Output port of alarm
2 Output port of battery status
3 Output port of bypass status
4 Input port of remote EPO*
Output port of bypass
5
backfeed
Note*:
Pin1 and pin2, or pin3 and pin4 of the dry contact port 4 reserves the corresponding terminals for configuring the REPO function. The
REPO device also needs the shielded cable to connect to the normally open/closed remote REPO switch between the two terminals. If not
necessary, you should disconnect pin3 and pin4 of the dry contact port 4, or short pin1 and pin2 of the dry contact port 4. Pin1 and pin2 of
the dry contact port 4 have been shorted before delivery
The EPO action of the UPS will stop the rectifier, inverter and static bypass, but it cannot disconnect the UPS mains input inside. If you want
to disconnect the UPS completely, just disconnect the upstream input MCB when generating the EPO.
In emergency conditions, close the REPO switch (prepared by users) to shut down the rectifier and inverter, and the UPS is
powered off. In normal condition, the REPO switch cannot cut off the UPS input power. If a switch of electronic control tripping
function is adopted at the UPS input, the REPO switch can help the switch trip and thus cut off the UPS input power. The
position of the REPO switch is shown in Figure 1-3, and the REPO cable connection is shown in Figure 7-3.
REPO switch
The cable connection procedures are as follows:
1. Loosen the "+12V" and "EPO_IN" connection terminals of the REPO port.
2. Insert the two ends of the copper core cables with the insulation stripped back into the "+12V" and "EPO_IN" connection
terminals of the REPO port, and press down the terminals. The REPO cable is complete. Ensure that the REPO cable is firmly
connected to avoid no action or wrong action of the REPO caused by accidental dropping or rough handling.
3. For parallel UPS, when connecting the REPO cable, users should parallel connect "+12V" of the REPO port with one end of
the electronic switch, and parallel connect "EPO_IN" with the other end of the electronic switch. Note the difference between
the port silkscreen "+" and "-" during connection.
When the REPO switch at the user end closes, the UPS will generate an alarm and cut off the output immediately, and the UPS
will not return to the normal operation state automatically. At this point, you must change the REPO switch state, and power
on the UPS manually.
56
Pin NO. Pin name
1.1 S_ALARM The signal level is 12V when the system alarms
1.2 GND GND
2.1 ON_BATTERY The signal level is 12V when the system runs in battery mode
2.2 GND GND
3.1 ON_BYPASS The level is 12V when the system runs in bypass mode
3.2 GND GND
4.1 EPO_NC EPO activated when opened to 4.2
＋12V
4.2 EPO activated when opened to 4.1
＋12V
4.3 EPO activated when shorted to 4.4
4.4 EPO_IN EPO activated when shorted to 4.3
Bypass backfeed protection relay (normally open). Closes when
5.1 BFP_O short circuit of bypass silicon controlled rectifier (SCR) leads to
backfeed
5.2 BFP_S The middle point of the bypass backfeed protection relay
Bypass backfeed protection relay (normally open). Opens
5.3 BFP_C
when short circuit of bypass SCR leads to backfeed
Note
Figure 7-3 REPO cable connection
Meaning
REPO plug
User Manual 10H52188UM60 - Rev. 2 - 09/2012
Liebert NXC