8
Installation
Siting considerations
Before unpacking and installing the unit, consider the following:
■ DO NOT expose the UPS to high temperatures, water ingress, flammable or corrosive gas, dust,
direct sunlight or explosives.
■ Locate the UPS indoors on a level surface as close as possible to the equipment it will be powering to
minimise cable voltage drops. Allow enough spare cable to move the UPS and access the rear and
side panels during servicing.
■ Maintain a gap of at least 20 cm from walls or other equipment and ensure the ventilation holes/slots
at the front and rear of the units are not obstructed.
■ For maximum battery life and improved product reliability ensure cool air is available at the front of the
unit. As an approximation, battery life is halved for every 10°C rise in temperature.
Wiring considerations
To ensure a safe installation please follow these instructions and the local electrical code of the area or
country in which you are installing the equipment:
■ If the UPS is to be supplied from a local transformer, ensure the transformer kVA rating is at least
50% greater than the UPS output kVA rating.
■ Use circuit breakers and cables with the correct rating (see the next section).
■ Always fit an MCB between the mains supply live line only and the UPS input (see Figure 2).
Caution:
Do not fit an MCB in the neutral line.
■ Because of the high leakage current, permanently hard wire all the a.c. cables or use industrial
connectors (not domestic connectors).
■ Use ring terminal crimps on the end of all cable conductors to ensure the connections are secure.
■ If using external batteries, always fit a 3 pole MCCB, with a suitable d.c. voltage rating and breaking
capacity, between the battery and the UPS (see Figure 2).
Caution:
The UPS is designed to work with a centre-tap battery only.
■ Although it may not be absolutely necessary, we recommend you fit an MCB between the UPS and
the load to protect the output load and cables in the event of a fault (see Figure 2). You may also wish
to connect the UPS output to your load via a distribution unit (PDU).
Figure 2 Power cable wiring configuration for a single UPS
VFI-KT Series User Manual
