DiversiTech Definite Purpose Contactor C330B

The DiversiTech C330B is a three pole definite purpose contactor rated 30 amps with a 120 volt coil.

Testing a contactor properly requires more than checking whether it pulls in. A useful sequence covers three things.

First, the coil: measure its resistance with the circuit de-energised. An open reading means a failed coil; a reading close to zero suggests a shorted one. Compare against the manufacturer's figure where available.

Second, the mechanical action: with power off, press the armature closed by hand and confirm it moves freely and returns fully under spring pressure. A sticking armature, from dirt, corrosion, or insects, produces intermittent operation that no electrical test will reveal.

Third, the contacts under load: with the equipment running, measure the voltage drop across each pole from line to load. A sound contact shows negligible drop. A measurable drop across a closed contact indicates resistance, which means heat and a contact approaching failure. This test finds deteriorating contacts before they cause a breakdown, and it is more informative than visual inspection alone.

Testing all three poles matters on a three phase contactor, since one deteriorated pole can single phase the motor.

Applications include commercial air conditioning and refrigeration equipment with line voltage control.

Brand

DiversiTech

SKU

C330B

Category

Contactors

Weight

1.05 lbs

Dimensions

3.50" x 2.80" x 2.40"

Price

$28.00

Availability

In stock (4 available)

Rating

4.38 / 5.0