KMC Controls XEE-6311 - Manual (Page 2)

KMC Controls
AN0604D Revision B
Tips for connecting 24-volt power
Choosing a transformer
1–16
Mounting Transformers supplied by KMC Controls may be either foot or
knock-out mounted. Foot mounting is usually used inside of an enclosure.
Knock-out mount attaches the transformer directly to a conduit fitting such as a
cover plate for a handy-box.
Circuit breaker
(optional)
Bracket for foot
mounting
Threads for knock
out mounting
Primary voltage The primary voltage rating of the transformer must match the
voltage of the AC mains to which it will connect. Transformers are manufactured
for either a single primary voltage such 120 or 240 volts or multiple voltages. The
two XEE–6000 series transformers in Illustration 2 are examples of both types of
primaries.
Common
240 VAC
120 VAC
277 VAC
480 VAC
Circuit Breaker
24 VAC
–
120 VAC
24 VAC
Circuit Breaker
– Common
Single voltage primary transformer Multiple tap primary transformer
Secondary voltage The secondary voltage for KMC transformers is 24 volts AC.
Some transformers include an optional circuit breaker which protects the
transformer and wiring from current that exceeds the capacity of the circuit
components.
Load capacity The load capacity is a measure of how much power the
transformer can deliver to attached devices. This is usually expressed as VA, an
abbreviation for Volt-Amperes. See
Calculating transformer size on page 1-21 for
additional information on transformer load capacity.
Illustration 1 KMC XEE–6000 series transformer
Illustration 2 Transformer schematics