DSPM Defender 3 - Page 17

1.6.C. AC Loss/Battery Operation
Referring to Figure 3, if the input power is interrupted, the battery will immediately supply the DC power required by
the Inverter to maintain continuous AC power to the load. A fully charged battery will provide power for the specied
time at the rated load, or longer at reduced load.
In the event of a power failure, the rectiers will de-energize and the batteries will discharge into the Inverter and
maintain power to the critical load until a) the battery capacity expires and the inverter turns off, or b) input power is
restored after which the rectiers will power the inverter and simultaneously recharge the batteries. Figure 3 illus-
trates the ow diagram during battery operation.
When power is restored after a low battery shutdown, the rectiers automatically restart and, recharge the batteries
and the Inverter is automatically restarted without operator intervention. The inverter automatically without operator
intervention assumes the power from the Rectier.
1.6.D. External Maintenance Bypass (EMB) Operation (Optional)
There is an optional External Maintenance Bypass which supplies the critical load with unconditioned input power .
The purpose of this option is to route power to the critical load while the UPS’ rectier and inverter are de-energized,
and during Start-up before the system is fully operational (refer to Figure 4).
With the External Maintenance Bypass there is a hard wired bypass that can be operated after the Static Bypass
Switch has been operated, making it possible to isolate the entire UPS for service and maintenance. The internal
control system determines the operation of the normal and External Maintenance Bypass paths, with the load pow-
ered from the inverter being the normal operation.
Figure 4 Single Line Drawings –External Maintenance Bypass Operation
Figure 4 Single Line Drawings –
Title: Micro
Doc No.: 018-1000-02
Description: Emergency Lighting Inverter User’s Manual Date: 07/26/2016
Rev: NR
1.877.DSPM.POWERPhone : 1.877.377.6769-
909.930.3335Fax:
www.dspmanufacturing.com
Website:
techsupport@dspmanufacturing.com
E-Mail:
17
Title: Three Phase 208 or 208Y/120Vac
Doc No.: 018-6000-00
Description: Emergency Lighting Inverter User’s Manual
Rev: NR
Date: 08/12/2022
Phone :
Website:
E-Mail:
Fax:
1.877.DSPM.POWER-1.877.377.6769
1.877.DSPM.POWER-1.877.377.6769
www.dspmanufacturing.com
techsupport@dspmanufacturing.com