Heat Coil Pin Wiring Order: XLR Plug Match Guide

By January 4, 2019 August 17th, 2019 E-Nail Gear

XLR Plug Matching Guide: How to Find a Heat Coil Pin Wiring Order

When switching out heating coils for your e-nail, the most important thing to do is make sure that the heat coil pin wiring order matches your controller. If you don’t then your e-nail probably won’t work, and you might end up with a hot mess!

Proprietary Shenanigans:

Just because the XLR plug fits does not necessarily mean that it is compatible. Some e-nail makers came up with their own proprietary XLR wiring order to try to win repeat buyers. This causes more headaches than anything else. Read on for options on remedies for this frustrating situation we find ourselves in.

The easy way to find your heat coil pin wiring order:

The first and easiest way is to e-mail the company you bought your original gear from. Ask “Will you please tell me what the wiring order is for the pins 1-5 on the XLR plug? They understand what you mean. E-nail companies are upfront and transparent about how the heat coil is wired the majority of the time. There’s not much reason to guard this information, unless they are really trying to keep their wiring type proprietary. 

Your right to know:

It’s for your safety’s sake that you know, so it’s pretty reasonable to be asking. They should comply because it’s a safety concern for the customer if they buy mismatched replacements. It’s not like you are asking Coke for the secrets to the recipe or anything! In reality proprietary wiring for coils don’t do much for brands except confuse and frustrate customers. They may get a few repeats from certain customers but overall it’s more of an annoyance than anything. It would be much better if we all stuck to the same wiring order “standard”.

e-nail heat coil matching guide for beginners

Take matters into your own hands…

Online sellers disappear. Ebay sellers are at times unresponsive. If you don’t get a response then take the bull by the horns and find out for yourself! A “quick diagnosis” on the heat coil plug is not as hard as it sounds. You will come out with the information you need to replace your gear as well as a new skill.

How to find your heat coil pin wiring order (the manual way):

First, unscrew the plastic piece from the metal plug on the end. See the pictures below for an illustration of where to twist. Now, pull the plastic piece back with the protective sheath to reveal the inside. You will see a plastic guard that goes around the soldered pins. Carefully pull the whole piece out of the metal housing and remove the plastic guard. Note: the plastic guard can be stiff and tricky. If you break it just use one thin layer of electrical tape to wrap around the pins once. Note: too much tape will make it hard to replace inside the metal housing.

XLr plug wiring
XLR plug wiring
XLR plug wiring
XLR plug wiring

Fully Exposed: Thermocouple Wires

Now you should be able to see 5 different wires connecting to metal pins. Some of these wires vary in thicknesses and/or in color (hopefully). Look to find the two wires that are thinner than the other three. If you see a pair of thin red and black wires, they are probably the TC’s. We’re more than halfway there!

Ground and AC Power Lines:

Try to see if you can spot one odd wire that is not like any of the others to single out the ground first (it’s easiest). The two remaining thicker wires are probably AC power, which are normally interchangeable (since AC is non-polar). DC power runs to the TC’s (which do have polarity) so positive and negative need to be connected to their matching spots on the controller. 

Polarity: Which is TC+ and TC-?

Next, you will find out which of the TC’s is positive and which is negative. Normally the red is positive and the black is negative. If you are sure that you have the TC lines and not the AC lines, you can safely do a trial and error test. You can be reasonably sure of this if there is one set of thick wires and one set of thin wires. 

Cooling or Heating

You know the TC’s are backwards when the temperature display falls instead of climbs as the coil heats up. Temperature readings will quickly fall below zero and start reading negative temperatures. Now you also know how to make a DIY fridge or freezer using these controllers to maintain cool temps as well!

I can’t recommend DIY’ing this if you are not experienced with electronics or electric work. If you are experienced, however, keep reading for instructions:

Twist method (if you are in a pinch without access to a soldering gun):

Before you cut any wires it’s a very good idea to label any with tape to keep things straight. You’ll thank me later! If you forget to do this you can always do a simple continuity test with a number of cheap devices found at hardware stores, Harbor Freight, and others. Pull the fabric cable sheath back to expose, snip, and strip the wires bare. Now refer to the quick diagram you made and connect the connections where they need to go. Use a very thin wrapping of electrical tape or very thin shrink tubing to protect.

Pro Tip:

It’s best to cut the wires in different spots just to minimize any future chance of shorting. This also makes it easier to get the cable sheath to slide back over the wires later on. At this point I like to make a little diagram with two columns of #1-5. One column represents the e-nail controller and one column represents the heating coil. Then I draw and connect the appropriate connections to make sure everything is straightforward. Measure twice, cut once as they say!

Questions? Comments? Feel free to drop a line.