Energy Tech Laboratories EDP70 manual Operational modes, 24/36kVA Ratings

1.5Operational modes

S3 Maintenance By-pass

S2
S1	LOAD
AC Supply	S4

Battery	24/36kVA Ratings
Contactor
S3	Maintenance By-pass

S2	S5
	480Y/277V
	LOAD
S1	S4
AC Supply	208Y/120V
Battery
Contactor	50/80kVA Ratings

Figure 3 – Normal operation

During normal operation the load is supplied by the mains through the rectifier and inverter. The rectifier also supplies the current for recharging and maintaining the battery in a fully charged state.

S3 Maintenance By-pass

Reserve Supply	S2
	S1	S4	LOAD
AC Supply
		Battery
		Contactor

24/36kVA Ratings

S3 Maintenance By-pass

Reserve Supply S2 S5

S1	S4
AC Supply
Battery	50/80kVA Ratings
Contactor

480Y/277V

LOAD

208Y/120V

Figure 4 – Utility Supply failure

When the utility supply voltage is absent or outside the allowed tolerances, the battery supplies the inverter. This will be indicated on the UPS front panel display and the Remote Alarm Unit (if fitted). The standby time available depends both on the capacity of the battery and on the size of load. It is possible to extend autonomy by reducing the output power by disconnecting non-important loads. In all cases, the alphanumerical display shows the residual autonomy.

MI00/10056 rev.1--05/2001-- page 9