Discussion Category:  PCR / Thermal Cyclers

Tracing down Power Error Masteracycler Gradient

I have an Eppendorf Masteracycler Gradient 5331. It shows "Power ERR" I've traced it down to no input on the octocoupler on the power board that turns on the 28v peltier board. The signal for the octocoupler comes from the larger board through pin 4 on the ribbon cable to the octocoupler. That traces back to an NPN fet. I get no signal. At startup there is a signal for about 5 seconds then it shuts down. Does anyone have any input to save me hours in reverse engineering. It seems like a bad clamp circuit, pull down resistor or something. Any help would be greatly appreciated. Thank you.
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tech_8722
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dsetty

I have the same issue Power Err issue. It sounds like a known issue as the Service Manaul states there is a newer "Power Unit PCB." The manual explains that "these PCBs have been modified to eliminate the „Power Error“." This leads me to believe the Power PCB is repairbale. Were you ever able to trace back the error? Thanks!

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tech_8722

I was not. I'm waiting until we get a newer unit in with the updated pcb to compare. Right now it is sitting on the shelf. One thing I didn't check was the inrush limiter. I'll post once it is figured out. 

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xcontrol1000_9188

Dear Mr. Tech 9722

I have 1 Mastercycler 5331 and
a 5333 with the same "POWER error"

In the 5331 I made a short in the input of the optical coupler
It no longer displays the "POWER error"

However, it does not feed the peltiers

Please, can you help me

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