Warning: My boss told me to always use 22/4 wire for keypads, but it bit me on a big job

My old boss at the company in Phoenix swore by using 22/4 stranded wire for every single keypad run, saying it was the standard and you'd never have voltage drop issues. I followed that advice for years. Then last month, I was wiring a massive 5,000 square foot house with keypads over 150 feet from the main panel. I used the 22/4 like always, and two of the keypads kept glitching, showing low power errors. A senior guy from another crew came to help and took one look. He said for runs over 100 feet, you need to step up to at least 20/4 or even 18/4 to account for the resistance. We had to re-pull wire for those two runs, which added a full day to the job. So now I'm torn. Was my boss right for keeping it simple and standard, or is it better to always check the run length and upsize the wire? What's your rule of thumb for keypad wire gauge?

3 comments

3 Comments

davis.gavin1mo ago

Used to follow that exact same rule, thought 22/4 was the golden standard for every keypad. Got burned on a long run in a warehouse retrofit where the keypads were acting up. Now I always check the distance first. My rule is to use 22/4 for under 75 feet, 20/4 up to about 150 feet, and I'll jump to 18/4 for anything longer than that. It adds a step to the plan but saves a huge headache later.

mary_wells1mo ago

Voltage drop matters more than just distance though.

the_sarah21d ago

Honestly feels like people are overthinking this sometimes. Davis.gavin's rule is fine but most keypads just work if you use decent wire. Voltage drop is a real thing but how often does it actually cause a problem in a normal house? Seen plenty of installs with thin wire on long runs that are just fine for years.