Would this work on a Mercedes benz s430 airmatic compressor

is it 40 amps or less then it should

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

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.

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

Product ID: 4141102

Details

Connector Type
Quick Connect
Contact Material
Silver Nickel
Contact Type
Normally Open
Current Rating
40 A
Mounting Type
Chassis Mount

⚡40 Amp max current

💧Moisture-resistant molded case

🔌Four 1/4 inch spade connectors

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Description

⚡ Elevate your 12V compressor game with power and precision!

PRECISION MOUNTING TABS - Integrated tabs for hassle-free, stable chassis installation
QUICK CONNECT TERMINALS - Four 1/4 inch spade posts for fast, secure wiring
BUILT TO BRAVE THE ELEMENTS - Moisture-resistant casing ensures durability in any environment
POWER PACKED 40 AMP CAPACITY - Handles heavy-duty 12V compressor loads with ease
RELIABLE AUTOMATIC OPERATION - Designed for seamless, maintenance-free compressor relay control

The Viair 93940 is a robust 40 Amp, 12 Volt air compressor relay featuring four quick-connect spade terminals and a moisture-resistant molded case. Engineered for reliable automatic operation, it includes integrated mounting tabs for easy chassis installation, making it an essential upgrade for professional-grade compressor setups.

Specifications

ASIN	B000YC7GBU
Best Sellers Rank	#46,323 in Automotive ( See Top 100 in Automotive ) #4 in Automotive Replacement Air Conditioning Compressor Relays
Brand Name	VIAIR
Coil Voltage	12 volts
Connector Type	Quick Connect
Contact Current Rating	40 A
Contact Material	Silver Nickel
Contact Type	Normally Open
Current Rating	40 A
Customer Reviews	4.7 4.7 out of 5 stars (630)
Global Trade Identification Number	00818114009402
Included Components	Per Item Description
Item Weight	22.68 g
Manufacturer	VIAIR
Maximum Switching Current	40 A
Maximum Switching Voltage	12 volts
Minimum Switching Voltage	12 volts_of_direct_current
Model	93940
Mounting Type	Chassis Mount
Number of Terminals	3
Operation Mode	Automatic
Part Number	93940
UPC	818114009402
Unit Count	1 Count
Warranty Description	All VIAIR products come with a One Year Manufacturer Defect Warranty
Wattage	480 watts

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HK$97

Duties & taxes included

In stock

Sold byAmazon Hong KongDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

Buyer Protection · Full refund if your order doesn't arrive as described.

Desertcart purchases this item on your behalf and handles shipping, customs, and support to Hong Kong.

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TrustScore 4.5 | 7,300+ reviews

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