UPS for 208 Vac Grid, B60US-IB Installation Guide, doc. rel. 3.0
77
Figure 60: The static switch in context (stand-alone system)
When two or more UPSs are configured in parallel mode, the static switches are synchronized by
dedicated control communication to ensure that if one unit goes to bypass mode, the rest of the
units will also transfer to bypass mode simultaneously.
To avoid such a hazard in decentralized mode, the static switches are synchronized by dedicated
control communication to ensure that if one unit goes to bypass mode, the rest of the units will
also transfer to bypass mode simultaneously.
6.1.2.
Parallel communication
When two or more UPS units are operated in parallel, parallel communication must take place
between them in a "ring configuration" arrangement. This is accomplished by the use of
Gamatronic-provided cables with D25 connectors on each end. Parallel communication keeps the
parallel units synchronized with each other and is used to pass commands and status information
between units.
Each UPS has two D25 parallel communication connection terminals.
Figure 61 below shows how to connect the parallel communication terminals for parallel
operation of two and three UPS units. When connecting one UPS to the other, it does not matter
which of the two D25 terminals you use on each UPS.
Summary of Contents for B60US-IB
Page 4: ......
