Can I use 20 gauge wire for my Mk2a Heatbed?


I purchased the following wire for my MK2a heated bed:

McMaster Carr 1 8209K11 840 Degree F Braided Oven Wire 20 Gauge, Tan, 10 ft. Length 1

Will this be acceptable? I'd like to print with ABS, which I know that the heatbed has to be hotter than when printing with PLA.


Posted 2016-03-25T13:09:16.460

Reputation: 1 853

I noticed that your question has not had much activity lately, are you still looking for an answer to this question? How might we be able to close some gaps? – tbm0115 – 2016-07-03T20:21:18.480

@tbm0115 please wait...I'm still learning more anout power on a question on another SE site:

– leeand00 – 2016-07-03T22:05:35.760



Your wire should be rated for at least the necessary 11 amps which the MK2a heatbed is supposed to take.

You can check this by measuring the resistivity of your wire:

Always test the heatbed wiring for resistance. Remember, at 10A, 0.1Ohms means 1V voltage drop means 10W dissipated by the wiring!

as taken from,493405 (useful read for seeing what CAN actually happen)

Did you read through the following links? They might clear up some questions:'s_guide

I personally would use 1.5 mm² cables, which translates to about 15 gauge wire.

*edit: This is a nice table to check:


Posted 2016-03-25T13:09:16.460

Reputation: 2 804

Is a higher wire gauge a thicker wire gauge? (here:,493405)

– leeand00 – 2016-03-25T15:28:32.513


lower wire gauge number means thicker wire. Here you can translate it to metric units:

– kamuro – 2016-03-25T15:31:12.533

If you're in the US, 14AWG is commonly available and will suffice for a continuous load of 11A. 14AWG is rated (by building code, not necessarily relevant here) to 15A intermittently or 12A continuously. – Hari Ganti – 2017-03-31T21:21:51.763