Figure 22. Principle of paralleled UPS systems
A Bypass inputs to UPSs
1
UPS 1
7
Battery
B Outputs from UPSs
2
UPS 2
8
Battery
C Load
3
UPS 3
9
MOB1
4
UPS 4
10
MOB2
5
Battery
11
MOB3
6
Battery
12
MOB4
The required parallel system wiring length must be equal to ensure
approximately equal current sharing when in the bypass mode.
For proper operation, the following must be true: 1A+1B=2A+2B=3A+3B=4A
+4B.
Any differences in wire length result in decreased capacity and improper
operation of the UPS system while in the bypass mode.
5.6.2
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)
Eaton 91PS/93PS UPS 8–40 kW
User's and installation guide
©
Eaton Corporation plc 2018. All rights reserved.
Revision: 005
Document ID: P-164000493
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