DC 12 40A relay for heating mats with base

Relay for controlling 12V heating mats

The relay enables safe connection of a set of heating mats to a BMS equipped with a heating mat control function.

Typically, BMS “Heat” outputs can carry a maximum current of 2-3A, hence the need to use a relay.

The set of heating mats for a 12V battery that we recommend has a power of 5x27W, which translates into a current of over 11A.

This is definitely too much to connect directly to the BMS.

The offered relay allows for transfer of current up to 40A.

It is equipped with a ready-made base with appropriately selected cable cross-sections (16 and 22AWG).

Additionally, a diode is used to protect the BMS output.

IMPORTANT:

Due to the presence of the diode, the correct polarity of the connection must be observed – the white wire is the positive coil control.

• Lifespan: 10,000,000 switching operations
• Switch-on time approx. 10ms
• Length of socket wires approx. 19cm
• Relay dimensions 28.5 x 28.5 x 25 mm

• The relay is very solidly made and has copper-plated contacts.
• Fits very well with the socket
• The thick 16AWG and 22AWG socket wires allow for the real transfer of high current.

The relay has 5 contacts

• we connect the coil switching voltage to contacts 85, 86 (black and white wires).(white is a plus).
• the coil shorts contacts 30 and 87 (blue and yellow wires) NO
• the coil opens contacts 30 and 87a (blue and red wires) NC
• the protection diode is connected in a reverse direction between pin 85/86.