Mars Spno-Spnc 24V Relay M90380

The Mars M90380 is a relay with single pole normally open and single pole normally closed contacts, operating from a 24 volt coil.

The separate normally open and normally closed contact arrangement provides two independent circuits with opposite actions, which differs from a changeover arrangement where both contacts share a common terminal.

Independence matters where the two circuits must be electrically isolated from one another. A changeover contact set has a shared common, so the two circuits are connected at that point. Separate contacts allow one circuit at one voltage and another at a different voltage, or a control circuit and a signalling circuit to a building management system, without any electrical connection between them.

This is a genuine requirement in some control schemes and a source of trouble when overlooked. Wiring two different voltage circuits through a shared common results in one supply appearing where it should not.

Where isolation is required, the relay's contact arrangement must provide it, and confirming whether contacts are independent or share a common is worth checking against the relay's data rather than assuming.

Applications include residential and commercial HVAC and refrigeration control circuits, interlocks, and equipment status signalling.

Brand

Mars

SKU

M90380

Category

Relays

Weight

0.3 lbs

Dimensions

2.50" x 1.90" x 1.60"

Price

$22.00

Availability

In stock

Rating

0 / 5.0