MYERS MP Series, Installation, Operation & Maintenance Manual

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On Line Mode: The utility power (120VAC, 60Hz) is fed through the MP2000E. The BBS
module senses and qualifies the external utility power. The inverter is switched off and
the battery charger is switched on. All loads attached to the MP2000E AC output terminal
will operated directly on the external utility power.
The Manual ByPass Switch module (MBPS)- This is the second component in the BBS
system. The switch is rated at 120VAC and 40 amps. This stand-alone switch is used to
manually isolate the MP2000E BBS module from utility power and the intersection
controller during maintenance and BBS replacement operations without turning off
power to the loads.
The Power Transfer Switch (PTS) is the third module in the BBS system. The PTS is rated
at 120VAC and 40 amps. MP2000E sends a 48VDC signal from the batteries to the PTS,
which activates the PTS, resulting in transfer from Input power to BBS power. The PTS
ensures that a continuous flow of power reaches the traffic controller cabinet. In the event
of a battery failure the 48 VDC is absent from the PTS. At that point the relay automatically
switched to the utility position. Upon restoration of utility power the external power will
flow to the traffic cabinet.