DiversiTech Transformer 40VA Class II Tran PF40224

The DiversiTech PF40224 is a 40 VA Class II control transformer for HVAC control circuits.

A control transformer steps line voltage down to the 24 volts at which HVAC control circuits operate. That low voltage is what allows a thermostat to be a safe, small device connected by light cable, and what allows safety controls to interrupt a circuit without switching line current.

The VA rating is the transformer's capacity, and it is the specification most often gotten wrong. VA is volt-amperes, the product of voltage and current, and it must exceed the total demand of everything the transformer supplies.

Calculating that demand requires attention to inrush rather than sealed VA. A contactor coil draws substantially more current at the instant of energising, while its armature is still open, than it does once closed. Where several devices energise simultaneously, the combined inrush can exceed the transformer's capacity even though the steady load is well within it.

The symptom is contactors that chatter or fail to pull in, appearing intermittently and under particular combinations of demand.

Class II designation indicates an inherently limited output meeting the relevant safety standard.

Applications include residential and commercial HVAC and refrigeration control circuits.

Brand

DiversiTech

SKU

PF40224

Category

Transformers

Weight

1.5 lbs

Dimensions

3.80" x 2.60" x 2.30"

Price

$25.00

Availability

In stock (2 available)

Rating

0 / 5.0