failed T-962A - Page 1
Forum section: electronics / general

author: djacobow
author_rank: Super Contributor
timestamp: June 10, 2021, 08:10:24 pm
content: On my recommendation, a friend bought a T-962A reflow oven, and it failed on the second run. Made a long beep and then no heat after that.I've had the same unit for a couple of years and though I'm not thrilled with the box, it works and I've not had a problem like this.On his unit, the control board seems to function. The screen, buttons, and temp sensing are all working. When he starts it the "lamp" light comes on, but not actual heat.I'm suspecting that either there is a wiring fault, SSR fault, or maybe an open in one of the quartz elements. Unfortunately, I can't easily visit him to help him debug it. He's not thrilled about poking around on AC stuff, either.Has anyone else seen T-962 failures and might have a strong suspicion about what needs changing?

author: jpanhalt
author_rank: Super Contributor
timestamp: June 10, 2021, 10:41:30 pm
content: I have a T962 (small tray) that I updated with the United Engineering software (see here:https://github.com/EccentricWkshp/T-962-improvements) before actually using it. Is yours or your friend's updated? I assume neither.I have not had any failures, nor have I read about anything like you describe. I concur with your suspicions. You might limit the possibilities by disconnecting one of your quartz heaters and see whether that duplicates the symptoms.

author: IanJ
author_rank: Unknown
timestamp: June 10, 2021, 10:43:28 pm
content: For info, Estechnical.co.uk do an upgrade kit for the T962A which I fitted on my one.....quite a lot better than the original control hardware.Might be an opportunity to upgrade.

author: djacobow
author_rank: Super Contributor
timestamp: June 10, 2021, 10:56:29 pm
content: Quote from: jpanhalt on June 10, 2021, 10:41:30 pmMy oven has the Unified Engineering fw, his does not. He wanted to try it for awhile with the stock firmware so he could better understand why he doesn't want it.I also did all the other "regular" changes: cold junction compensation, replacing masking tape with kapton, removing paint for ground. He hadn't yet done any of that.But anyway, the think isn't powering up the heaters at all, so I don't think fw is at issue.

author: djacobow
author_rank: Super Contributor
timestamp: June 10, 2021, 10:57:59 pm
content: Quote from: IanJ on June 10, 2021, 10:43:28 pmI was looking at that. Certainly, it makes sense if his controller board has failed. I strongly suspect cracked quartz element(s) or broken SSR. But I need to get my hands on it to find out. He's a few hundred miles away, so it'll be awhile before I can visit.

author: jpanhalt
author_rank: Super Contributor
timestamp: June 10, 2021, 11:08:54 pm
content: I don't/didn't think it is firmware either.My thought was there may be a check for whether both heaters are on (e.g., current sensor). Disconnecting one of your heaters would answer that. My impression of the UE firmware is that it is mostly additive, so the same check would probably be done as in the original.As for a failed SSR, that would be more difficult to pin down remotely.

author: asmi
author_rank: Super Contributor
timestamp: June 11, 2021, 01:58:26 pm
content: If it's within return window, get the seller to replace or refund it. Lemons do happen every once in a while, as long as the seller does the right thing, it shouldn't be that big on a deal.That said, my T962 oven served me well for several years, until I replaced it with ZB2520HL oven as I started working with larger boards and so needed larger oven. This one is the largest oven I was able to find that still works from regular 15A@110V household outlet without tripping the circuit breaker. That oven works well out of box without any modifications, despite it's rather unorthodox way of defining reflow profiles.