Verifying the correct wiring of the Scotle HR460 heating elements. - Page 1
Forum section: electronics / projects

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: August 04, 2016, 08:50:06 pm
content: Hello,Long story short, I purchased a used Scotle HR460C BGA rework station and it came broken. I replaced the broken ceramic heating elements with Elstein HTS/1 600 watt, 230v and Elstein HTS/4 150 watt, 230v.There's two switches for the zone on the side of the unit. One that says RIGHT HEATER, one that says LEFT HEATER. I'm trying to understand how the switches actually work and I'm having some trouble. I was hoping if I uploaded some pictures here, someone could help me figure out how the voltage flows from each switch to the various heating elements. As far as I can tell, both switches eventually go to every heating element. If I have one switch on, it looks like all heating elements are active. If I have both switches on, it looks like all heating elements are active. If I have both switches off, it looks like none of them are active. I don't think it's wired correctly.Also, before I took it apart to repair it, it appears that someone had taken it apart before. Some of the hex screws were stripped a bit, some screws were missing, etc.I'm thinking of trying to rewire it, but in such away where one switch turns on just the inside heating elements, and with the other switch on, it turns on the outside ones. That way, I can turn on one for smaller boards, or both for larger boards.Here's some pictures of the way it is now. I can try uploading better pictures. It's a bit hard to see with all the wires how it's all routed. I was hoping someone could show me how I'd wire it to have it the way I want it. I want it so in the New Elements picture, when both switches are on, all heating elements are active. When one of them is off, the outer two long elements are off (the left and right ones) I think.I can send more pictures if anyone needs them. In the other pictures (Switches and Bottom of Unit 1), the blue colour is the RIGHT HEATER switch and the purplish colour is the LEFT HEATER switch.Those ceramic terminal blocks, where the wires connect, they're connected straight through. For example, there's four holes where the wires go in. And if I have a wire going in on the top left side of one, whatever wire is connected to the top right side gets connected. The wires connected to the bottom ones are the same way. But if I have just one wire connected to a bottom hole and one wire connect to either of the top holes, they're not connected to each other. I hope I described that simple enough.Can anyone help me figure out how to properly wire this? Thank you!I appreciate any help.Thanks!

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: August 05, 2016, 06:51:42 pm
content: At this point, I have given up on rewiring the zones.I have decided that I just want to make sure the unit is properly wired now. I noticed that the original picture I had taken showed a wire in a different place from where I had it when I replaced the old heating elements. I switched that around and have created a block diagram showing how it's currently wired.I believe this is incorrect though. Do these heating elements have a polarity? Is one side positive and one side negative? If not, does the electricity go through one wire, up into the heating element's coil, generate heat and come down the other wire? From the original pics, I see the top heating elements had the wires crossed over. I'll upload a very crude basic drawing to show what I mean. At the time, I didn't think this was important and switched them around. The new elements wires aren't long enough. I didn't realize that when I placed the order and because it was an expensive order, I'd hate to have to just not use these and order even more, with longer wires.Notice in the second attachment, original top part.png, the two upper heating elements have their right most wires connected together. Does this actually matter? I figured they were sort of like big giant resisters that put off a lot of heat and it didn't matter which way they were wired together, in that sense.

author: Spork Schivago
author_rank: Frequent Contributor
timestamp: August 07, 2016, 04:17:23 am
content: Just wanted to update you guys and let you know I think I finally got it correct. I decided to go with the original wiring but because the leads weren't long enough with the new Elstein's, I had to rearrange some of the wires a bit, but from what I can tell, they're all properly connected now and all the wires are connected to the same wires they were originally connected to, just not in the same terminals, for example.I turned on my Scotle HR460C for the first time tonight and everything appears to be working! I bought this back in May. It just took a very, very long time to get everything I needed. Finally done!!!! Just gotta figure out how to use it now!Thanks :-P