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Products => Test Equipment => Topic started by: Abe Normal on January 23, 2019, 10:22:27 pm

Title: Siglent SPD3303C Floating Outputs or Not
Post by: Abe Normal on January 23, 2019, 10:22:27 pm
Hi All,

I just bought a Siglent SPD3303C and have some questions that I hope someone can help me with.

From the look of the front panel on the SPD3303C (i.e. it has a separate GND terminal) I assumed that the 3 channels were all floating. When I got the unit, I checked to confirm my assumption. But I found that the common on channel 2 was tied to GND (although channel 1 and 3 common terminals were not tied to GND). Then I tested the power supply in Serial and Parallel modes and in both cases channel 1 common was also tied to GND (when the outputs were turned on) - which is what I suspected would be the case.

So this means (if I checked correctly) that channel 1 is floating only when the power supply is operating in "independent" mode, channel 2 is never floating, and channel 3 is always floating.

So my questions are:


Thanks for lookin'
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Abe Normal on January 24, 2019, 05:54:55 pm
Did a little more digging and answered it myself.

Siglent Americas web site says "Triple Output with 2 Floating Outputs": https://www.siglentamerica.com/power-supplies/ (https://www.siglentamerica.com/power-supplies/)  :'(
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: rf-loop on January 24, 2019, 06:15:25 pm
Siglent C model data sheet: 3 independent controlled and isolated output

I  can not test this C model at this time but X and X-E models have all 3 outputs fully floating and this I know sure with my own measurements/tests.
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Abe Normal on January 24, 2019, 09:23:03 pm
Thanks rf-loop. I see what you mean (I have a copy of that data sheet).

Seems contradictory to the other statement I found on their web site. I'll see if I can get any clarification from Siglent but I suspect they'll say "working as designed".
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: tautech on January 24, 2019, 09:32:48 pm
Quote from: Abe Normal on January 24, 2019, 09:23:03 pm
Seems contradictory to the other statement I found on their web site. I'll see if I can get any clarification from Siglent but I suspect they'll say "working as designed".
IMO the channel isolation status claimed is quite clear but like rf-loop I don't have one in stock so to check 100%.
Email sent to Siglent America asking for them to confirm.
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Siglent America on January 24, 2019, 10:12:32 pm
PM sent
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Abe Normal on January 25, 2019, 08:17:07 pm
Thanks tautech!

I was contacted by a Siglent Americas rep and they confirmed that all 3 outputs should be isolated. I'm returning the unit to Amazon for replacement and, if that doesn't work out, the Siglent rep has suggested another avenue to get a properly functioning unit.

Hopefully, 2nd times a charm. I'll post again when I have the new unit in hand.

Thanks again for your help tautech and rf-loop.
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Calvin on January 26, 2019, 07:25:31 am
Hi,

I checked my SPD3303C and can confirm that all three outputs are isolated from GND and from each other.

regards
Calvin
Title: Re: Siglent SPD3303C Floating Outputs or Not
Post by: Abe Normal on February 04, 2019, 04:30:24 pm
Just wanted to close out this thread by reporting that the replacement unit I got from Amazon is working correctly (all 3 outputs are isolated).

I also want to say that the rep from Siglent America was very helpful  :-+ and gave me confidence in the brand (despite the rough start).