Xtreme Power Conversion Corporation
R91 User’s Manual
Page 10
Uninterruptible Power Supply
UPS Output
Any external distribution board used for load distribution shall be fitted with protective devices so as to avoid the
risk of UPS overload.
Over-Current Protection
A protection device shall be installed at the distribution panel of the incoming utility power, and should identify
the power cables current capacity as well as the overload capacity of the system.
CAUTION!
Select a thermo-magnetic circuit-breaker with an IEC 60947-2 trip curve D (normal) for 125% of the current as
listed below.
40A Input Circuit Breaker required.
Power Cables
The cable design shall comply with the voltages and currents provided in this section, and in accordance with local
electrical codes.
WARNING!
UPON STARTING, PLEASE ENSURE THAT YOU ARE AWARE OF THE LOCATION AND OPERATION OF THE EXTERNAL
ISOLATORS WHICH ARE CONNECTED TO THE UPS INPUT/BYPASS SUPPLY OF THE UTILITY DISTRIBUTION PANEL.
CHECK TO SEE IF THESE SUPPLIES ARE ELECTRICALLY ISOLATED, AND POST ANY NECESSARY WARNING SIGNS TO
PREVENT ANY INADVERTENT OPERATION
Cable Sizes
UPS MODEL
CABLE SIZES (THHW wiring at 75°C)
AC INPUT
AC OUTPUT
DC INPUT
GROUNDING
R91-20K
8 awg
8 awg
6 awg
8 awg
CAUTION!
Protective earth ground cable: connect each cabinet to an earth ground, following the shortest route possible.
WARNING!
FAILURE TO FOLLOW ADEQUATE GROUNDING PROCEDURES MAY RESULT IN ELECTROMAGNETIC INTERFERENCE
OR IN HAZARDS INVOLVING ELECTRICAL SHOCK AND FIRE.
Power Cables Connection
After the equipment has been properly positioned and secured, connect the power cables as described below.
Verify the UPS is totally isolated from its external power source and all circuit breakers to the UPS are open. Check
to see that everything is electrically isolated, and post any necessary warning signs to prevent inadvertent opera-
tion of the breakers.
