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Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor

Q: Would this work on a Mercedes benz s430 airmatic compressor

is it 40 amps or less then it should

Q: Will this relay work for a Mercedes R350

relays see amperage only, so if what you are trying to control does not draw more than the rated amperage of the relay, then yes

Q: I just bought this relay to go with the viair high flow 150 set up. But it only has a pos and neg wire will the relay work?

Yes it should work. The purpose of a relay is to allow the use of smaller gauge wire for the pressure switch input from the pressure tank and on/off switch, however, you need to use an appropriately sized wire from your battery or another high amperage source direct to the compressor. The item shown is for 40 amp delivery and if this is the draw for your compressor, you should be looking at wire in the 8 gauge range for both positive and to chassis ground or all the way back to the battery. If the compressor draw is less, like something in the 15 or 20 amp range, you can still use this relay and use 14 gauge (for 15 amp draw) or 12 gauge (for 20 amp draw) for the main positive and negative run to the compressor. As stated above, the ancillary wiring for pressure switch, on/off switch can be much smaller wire gauge. An internet search should have wiring diagram info for high amp devices and possibly the Viair website. Be aware that I am NOT an electrician so do not blindly follow my input. Hope this helps somewhat.

4.7/5

Product ID: 55607929

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Details

Connector Type
Quick Connect
Contact Material
Silver Nickel
Current Rating
40 Amps
Mounting Type
Chassis Mount
Brand
VIAIR

Frequently Bought Together

Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor , Black

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Viair 90223 Pressure Switch, Black 1/8 in. NPT (M) 12 gauge

Description

Viair 93940 40 Amp Air Compressor Relay for 12 Volt compressor

40 Amp 12v Relay with Mounting Tabs;Four 1/4 inch spade post connectors;Handles up to 40 amperes maximum ampere draw in applications;Each compressor must have its own relay for a proper installation;Mounting tab for relay molded into moisture resistance relay case

Have a Question? See What Others Asked

Would this work on a Mercedes benz s430 airmatic compressor

Will this relay work for a Mercedes R350

I just bought this relay to go with the viair high flow 150 set up. But it only has a pos and neg wire will the relay work?

Will it fit a R350

Common Questions

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