HP/Agilent 5890 Warning: Oven Shut off

[aidnai]

Sounds like you're doing some good troubleshooting. Good luck getting to the bottom of it!

[osp001]

I'm still confused about how to check the oven door mechanism.

Mea culpa. I had thought there was an actual switch there, but I got into mine last night to find out I was quite wrong. My apologies.

The best I could do was reproduce the error by leaving the door ajar, resulting in an inability to ramp the temperature up fast enough, so- nothing new there.

[antonk]

There is diagnostic/tuning mode for heaters (entered pressings [Stop] during boot) or using [.] commands (can not remember exactly).

When mainboard lost PID constants for heater - you can get such problem.
Try to re-calibrate oven sensor and heater.

[osp001]

Try to re-calibrate oven sensor and heater.

And for those playing the game at home, that's on page SVC 5-29:

https://www.ursinus.edu/live/files/140- ... -manualpdf

[juliandev]

Thanks for the further replies.
the oven and other temperature sensors measure room temperature reasonably.
I can only do a one point (re)calibration at room temperatures, since I can't heat up the oven.
I adjusted delta T by 0.1 K.

It didn't solve the problem.

[antonk]

Thanks for the further replies.
the oven and other temperature sensors measure room temperature reasonably.
I can only do a one point (re)calibration at room temperatures, since I can't heat up the oven.
I adjusted delta T by 0.1 K.

It didn't solve the problem.

Does the oven thermal sensor show adequate value when you heat it with the solder (~350C)?
Does the value increase monotonically when you heat the sensor or jumps?

[juliandev]

Currently the main PCB is removed from the GC so I can't observe the readings. I will respond on that as soon I replace it.

*** Update
We put the 5890 Series ii board into a working 5890 series i and could reproduce the error:
Oven not heating
Fan not running.

While playing around with the working 5890 series i and it's original main PCB, we found out that the contactor on the Power PCB in the back of the GC (picture on post from DEC 7th) gives a physical response to entering a temperature on the keypad. It clicks and creates a contact, you can both see and hear it. Again, as posted earlier, this contactor is main PCB controlled.

Right now, we are hunting for a replacement board, since this test again hints towards a main PCB issue.

I will give an update.

[KM-USA]

Right now, we are hunting for a replacement board, since this test again hints towards a main PCB issue.

I've got a fair amount of used 5890 parts from working units which were disposed of because they were no longer needed. Reasonable too, if shipping to within USA; but I can only do PayPal, money order or check, no credit card.

Post the part number(s) of what you are looking for, maybe even a photo too, along with your E-mail address. I'll post if I have that part, and I'll send you an E-mail asking you to make an offer.

[juliandev]

***update

swapped in replacement mainboard - system back running, no FAULTS, all heated zones get powered up.
visually, the faulty mainboard looks totally fine.

thanks for the offer KM-USA, unfortunately I read it after hunting on ebay. We have 3 5890s running, so who knows, what comes next.

Thanks to everyone for the steady support. I'll probably give another performance update after a couple of weeks.

[Consumer Products Guy]

We have 3 5890s running, so who knows, what comes next.

Three operating 5890 units? Maybe buy his entire stash of parts.

[aidnai]

Glad to hear you finally got to the bottom of it. Thanks for the update!