The output voltage of USB-3105 is lower than specified.

[LianhongZhu]

I find my USB-3105 can't output the specified voltage. For example, I adjusted the output voltage of channel 2 to 9.99 VDC in Instacal. But the measured voltage on USB-3105 channel 2 was only 3.x VDC. The other channels are the same. Seems they can only output 0~3.x VDC. What could be the reason?

[Fausto]

Hello @LianhongZhu.

What is the serial number of your USB-3105, as shown in InstaCal?

Has this module worked correctly in the past?

What is the history of this module?

Regards,

Fausto

[Fausto]

 

[LianhongZhu]

@Fausto The serial number of my USB-3105 is 91003. I received it from another team of our company. According to the shipper, it has been in idle for a long time.

I wired the VOUTx and AGND ports when measuring the voltage output. So I think the contact is OK, otherwise there will be no voltage measured.

 

[Fausto]

@LianhongZhu,

I do not see any physical damage or soldering modifications on either side of the PCB.  The firmware cannot be updated in the field, so the original firmware should still work.  If you verified that the wires were secured to the 'VOUT#' and 'AGND' screw terminals, then we are out of troubleshooting options, since this model cannot be repaired.