Eaton 9395 Maintenance Bypass Module Installation and Operation Manual
S
164201719 Rev 3
www.eaton.com/powerquality
1-1
Chapter 1
Introduction
The Eaton
®
9395 Maintenance Bypass Module (MBM) is designed for use with the
Eaton 9395 225–550 kVA three-phase uninterruptible power supplies. The MBM
enables power to completely bypass and isolate the UPS so that the UPS can be
safely serviced or replaced without interrupting power to critical systems.
The MBM is housed in a single, free‐standing cabinet with safety shields behind the
doors for hazardous voltage protection. The cabinet matches the UPS cabinets in style
and color. Figure 1‐1 shows the Eaton 9395 MBM.
NOTE
Startup and operational checks must be performed by an authorized Eaton Customer Service
Engineer, or the warranty terms specified on page NO TAG become void. This service is offered as part of the
sales contract for the UPS system. Contact an Eaton service representative in advance (usually a two-week
notice is required) to reserve a preferred startup date.
1.1
MBM Standard Features
The MBM has many standard features that provide cost‐effective and consistently
reliable power protection. The descriptions in this section provide a brief overview of
the MBM standard features.
1.1.1
Installation Features
The MBM can be installed in a
line-up-and-match
or
standalone
configuration and the
cabinet can be permanently bolted to the floor.
Power and control wiring can be routed through the top or bottom of the cabinet with
connections made to easily accessible terminals. External sensing and monitoring
control wire must be installed in accordance with Class 1 wiring methods.
1.1.2
Maintenance Bypass Breaker
An electrically controlled interlock maintenance bypass breaker (MBP) transfers the
load from the UPS output to the bypass input feeder.
1.1.3
Maintenance Isolation Breaker
An electrically controlled interlock maintenance isolation breaker (MIS) isolates the
UPS from the bypass feed and the load.
1.1.4
Customer Interface
The MBM uses UPS building alarm inputs for MBP monitoring. One alarm input will
detect when the MBP is closed and the system is on bypass.
1.1.5
Expansion
The MBM supports custom configurations and scalability to adapt to changing and
future power and distribution needs. See paragraph 1.2 for available options.
Figure