Always
O
n UPS Systems
M0703_NX_Series_Operators_Manual
V1.25
2012-06-12 49
10 INTERFACE
CONNECTIONS
All user interfaces are connected to or from PCB 3R, see the figure below.
10.1 Dry
Contacts
Eight, normally open, dry contact terminals are provided. Maximum rating of each relay is
16A/250VAC or 16A/30VDC.
Definitions:
•
INVON – Closed when inverter is on.
•
OVL – Closed when load exceeds overload limits.
•
FAULT – Closed when system encounters a fault condition such as: Rectifier high DC
shutdown, output short circuit, inverter fuse or over temperature condition, inverter overload
shutdown, emergency stop activation, inverter abnormal, and bypass on shutdown. The
contact is latched until it is manually reset (off switch) or the fault has been cleared for 30
seconds.
•
SS – Closed when the inverter static switch is active, open when the reserve static switch is
active. The two static switches will never conduct simultaneously.
•
BYPASS – Closed when the manual bypass breaker is closed, open when the manual bypass
breaker is opened.
•
BACK-UP – Closed while the system is in back-up mode (batteries supplying DC Bus).
•
BATL – Closed when low battery condition occurs and the batteries are about to be exhausted.
Figure 10.1.1
3R PCB Layout