User Manual

© 2016 Sensata Technologies
Page 47
Operation
Figure 3-5, Power Flow – Standby Mode (MS2000 models)
DC
OUT
120 VAC
AC NEU OUT
Neutral-Ground
Transfer Contact
AC Hot
Transfer Contact
AC HOT 1 OUT
AC HOT 1 IN
INPUT
(30A)
AC NEU IN
AC GROUND
Power Transformer
FET Bridge
AC
DC
DC POS
DC NEG
AC
OUT
120 VAC
AC
IN
Figure 3-4, Power Flow – Standby Mode (MS2012/2812/2024/4024/4048)
240
VAC
120
VAC
120
VAC
AC
OUT
Neutral-Ground
Transfer Relay
AC Hot
Transfer Relay
AC HOT 1 IN
AC HOT 2 IN
CB3 (30A)
AC GROUND
Power Transformer
FET Bridge
AC
DC
DC
OUT
AC HOT 1 OUT
AC HOT 2 OUT
CB2
1
CB1
1
DC POSITIVE
DC NEGATIVE
AC NEUTRAL OUT
240
VAC
120
VAC
120
VAC
AC
IN
Note¹: Output
breakers only
available on
MS2012-15B,
MS2012-20B, &
MS4048-20B
models.
AC NEUTRAL IN
3.2 Standby Mode
The MS Series features an internal battery charger and an automatic transfer relay when operating
in Standby mode. Standby mode begins whenever AC power (utility or generator) is connected
to the inverter’s AC input. Once the AC voltage and frequency of the incoming AC power is within
the AC input limits, an automatic AC transfer relay is activated. This transfer relay passes the
incoming AC power through the inverter to power the AC loads on the inverter’s output. This
incoming power is also used to activate a powerful internal battery charger to keep the battery
bank charged in case of power failure. Refer to Figures 3-4, 3-5, and 3-6 to see the fl ow of power
from the AC input to the DC and AC output while in Standby mode.