Looking for a part

Hi folks! I'm trying to find a component that I'm not familiar with.

See the attached photo. I'm looking for the piece that the yellow cable is wired into. It slides over four pins on the board to make a connection. The little white plastic piece is loose, so the connection is breaking. I just need to replace that one tiny piece, but I'm unfamiliar with what it's called or where to find them. Any help would be greatly appreciated. Thanks!

Terminal block. Not sure what particular style that is called.

Edit. Push comes to shove, you could swap the problem 4 terminal unit, for the 2 unused doubles from the opposite side.

Thanks, Glenn! And that's a great idea to simply swap those two. I wouldn't even need both, since only two on that 4 block are in use.

So these terminal blocks don't come in common sizes? Is there a way I can figure out what kind is the right one?

Crap. Wrote something and closed the tab....

Terminal block is what I'd call it too. Phoenix, Molex, Tyco etc.

http://au.mouser.com/ProductDetail/Phoen...c4htfacJcRrI%3d (Note that is the AU site)

Note that is for a two way version - the photo is generic.

Main thing to check is the pitch. I will bet it is 0.2" or 5.08mm.

I don't quite follow "It slides over four pins on the board to make a connection". Usually these are soldered directly into boards.

I can remove that block from the board. What's left are four pins sticking out that are soldered to the board. The pins go through the holes on the bottom, and the screws on top are what lock down on the wires pushed into the side (top is what you see looking at it, the side is perpendicular to that, but you get it...).

That's as well as I can describe it. I would have taken another picture but things were working again so I didn't want to mess with it.

Do a search on Google for "terminal block plug". Click "images". There is a dizzying array of such connectors.

You probably already ruled out a broken or cold solder joint on one of the four posts on the circuit board? If not, carefully touch up each of the four solder joints for that connector.

What is that interesting old circuit board for anyway? Zone valve controller? Home automation?

http://www.mouser.com/catalog/catalogusd/648/dload/pdf/intersection.pdf#page417 Pg 1818. Has something similar. Anyway the proper search terms are there.

This old board looks strikingly like something that would be featured on Bunnie Huang's "Name That Ware" blog feature (http://www.bunniestudios.com/). I'm going to make a wild-assed guess and say that it's a home alarm system controller. Modem for dialing out. Lots of pins for all the door/window sensors. On the other hand, 24V outputs? That's a weird number. Sprinkler valve controller? It's too high to be some kind of Christmas light controller.

Alarm system was my first guess, too. Something telephone related.

Throwing out a guess too, I'm thinking a little more HVAC related. Possibly tied to a datacenter with non water based fire suppression systems. Monitoring to allow measurement of AC or other systems use. Modem (unpopulated chip wise) for possible access during a power loss for monitoring purposes, less burglar alarm based.

I think it's a Tank Management System.

Tank? What kind of tank?

The Left 4 Dead kind of course.

I sort of miss that style of electronics: built with "discrete" components, that are fairly recognizable, with 0.1" pin pitch. Contrast that with circuit boards featuring one or two mysterious chips, the pins so close together you can't tell if they are touching.

Ah, the good old days.

I was researching outdoor PTZ cameras today, and a surprisingly large number of the higher end (eg. 20X, 30X optical zoom models) use 24VAC power supplies.

Looks like the metal mounting plate is attached to a cement block wall using explosively driven nails (aka Ramset , et al).

That metal plate is not coming off that wall...

Why would electronics be installed using such heavy fasteners?

Tom gets closest This building has an energy management system that's all computer controlled. The building owner called me because the software he uses to dial into the controller wasn't connecting. I found this panel, traced the lines and found that that block was loose. I got it back into place and it connected again.

In a way, you were all pretty close. His system controls the lights, HVAC, and sprinklers for the building. Pretty neat system.

I think I'll end up re-purposing the unused blocks like Glenn suggested. Then I can take the old block and maybe figure out how to get a replacement in case it's needed in the future.

That connector looks compatible with what embeddedarm.com uses for power on their touch screens. You might call them and ask what they use.