5.7.2
Control signals overview
2 controls signals (External CAN Network, Bypass Pull-Chain) are required for
external paralleling. Both of these control signals are fault-tolerant and alarmed
when disconnected.
External CAN (ECAN)
ECAN provides means for communication between the UPS’s in a parallel
system. When this network fails, the system continues to share load and protect
the load.
Bypass Pull-Chain
Bypass Pull-Chain is an open collector signal that goes low when the bypass
static switch of any UPS is online. When External CAN (ECAN) is down, the pull-
chain is low and the UPS is online, the UPS locks to and transfers to the bypass
mode. Service can manually short this signal in some rare failure modes to force
a system transfer to bypass.
Signal Inputs Actions
Each UPS has a maximum of 7 signal inputs, 5 native and one in each MiniSlot
when using a suitable connectivity device. These inputs can be configured with
action items. The following action items affect all the UPSs in the system. When
an action item is active on a UPS and the MOB is closed, the action item is
transmitted on the ECAN to all the UPSs.
Wiring the EPO switch in parallel
It is recommended to use separate EPO circuits for each parallel unit.
5.7.3
Installing parallel control wiring
1.
During the installation, follow all the safety instructions given in this
document.
2.
Terminal blocks TB2, TB3 and TB4 are for external parallel control signals
(see
Figure 26: Communication interfaces in the 15/20 kW standard and C-
and
Figure 27: Communication interfaces in the 30/40 kW
).
3.
The Phoenix Contact FRONT-MSTB 2,5/2-STF-5,08 and 2,6/4-SFT-5,08
plug components are used for cable wiring termination.
© Eaton Corporation plc 2020. All rights reserved.
Revision: 006
Document ID: P-164000493
73 (126)
Eaton 91PS/93PS UPS 8–40 kW
User’s and Installation Guide
