Siglent SPD3303X(-E) calibration FW1.01.01.02.07R2 - best practice

[jgartrel]

Some side notes:
- You cannot use EasyPower to send the SCPI commands. It seems to (intentionally?) botch the calibration commands. The best way is to use a telnet client (like https://putty.org/) to establish a telnet connection to port 5025. Or you can use NI VISA MAX instead. If you do, you must use "Write" in the NI VISAVisa Test Panel, not "Query".

With firmware version 1.01.01.02.07R2, I too had issues on MacOS using 'telnet' to connect to the device. Commands such as '*CALCLS 0' and '*IDN?' would work, but 'CALibration:VOLTage ch1,1,0.8613' would fail with a beep.

The calibration command would be accepted in firmware version 1.01.01.02.05, but the command '*CALST' (to store the new values) would fail.

I did have success using a Windows box with NI-MAX v5.4.1, but I was hoping for something that could be run without needing NI-MAX.

What eventually worked for me was to use 'netcat' instead of 'telnet' on MacOS. Following BreakingOhmsLaw recipe above, using the following sequence of commands from the Terminal in MacOS, I was able to successfully calibrate the device:

Code: [Select]

$ printf 'CALibration:VOLTage ch1,1,0.8613\n' | nc -w 5 192.168.X.X 5025
$ printf 'CALibration:VOLTage ch1,2,25.740\n' | nc -w 5 192.168.X.X 5025
$ printf '*CALST\n' | nc -w 5 192.168.X.X 5025
$ printf '*IDN?\n' | nc -w 5 192.168.X.X 5025
Siglent Technologies,SPD3303X,XXXXXXXXXXX,1.01.01.02.07R2,V3.0

When looking at what 'telnet' believes it is sending vs what 'netcat' believes it is sending, they look identical with 0x0a line terminations.  However, there must be more that I am missing here.

UPDATE: After a packet capture, it is apparent that 'telnet' is actually replacing the newline with CRLF behind the scenes. Toggling CRLF on/off in 'telnet' has no effect (CRLF is still sent). However, after configuring 'telnet' to 'set outbinary' via an escape command, the proper 0x0a line termination is sent and 'telnet' is usable.  This may also be a source of many other terminal programs also failing to send a properly formatted calibration command that the SPD3303X(-E) does not reject.

Thank you to BreakingOhmsLaw for all the hard work on putting this post together! I hope this additional info helps others on their journey.

[rolfdegen]

Houston, we have a problem!

Problem with new Firmware SPD3303X_V1.01.01.02.07R2.ADS 
After a while (> 1 hour) the power supply switches off the active channel 

My firmware vesion: SPD3303X_V1.01.01.02.07R2.ADS

[BreakingOhmsLaw]

Houston, we have a problem!

Problem with new Firmware SPD3303X_V1.01.01.02.07R2.ADS 
After a while (> 1 hour) the power supply switches off the active channel 

My firmware vesion: SPD3303X_V1.01.01.02.07R2.ADS

How old is your unit? The early version had a problem with a bridge rectifier overheating that was the cause for it switching off after some time.

[rolfdegen]

This is my Power Supply SPD3303X-E with hack for higher resulution. With the old firmware I had no problems with switching off 

[BreakingOhmsLaw]

Hardware version 3.0 has that rectifier bug.
If it's still under warranty, revert to old FW and have it repaired.

[orzel]

Hardware version 3.0 has that rectifier bug.
If it's still under warranty, revert to old FW and have it repaired.

Mine is version 3.0 as well, but i never had any problem.

Do you happen to know where we can have more information about this 'rectifier bug' ? Is that something easy to fix by ourselves ?

[rolfdegen]

The bug does not occur in the old firmware 1.01.01.02.05. The voltage and current are very stable. Fan speed is normal.

Video Siglent SPD3303X, hot bridge, hot regulators, modification for long life time

https://youtu.be/nvGxl44cNno

Hardware hotspot: https://youtu.be/mdOauVzY9OU?t=1651

I think the best way is a small fan for chip cooling 

[tautech]

Hardware version 3.0 has that rectifier bug.
If it's still under warranty, revert to old FW and have it repaired.

Mine is version 3.0 as well, but i never had any problem.

Do you happen to know where we can have more information about this 'rectifier bug' ? Is that something easy to fix by ourselves ?

Easy fix for any capable hobbyist...although the soldering might be challenging for those not experienced in lead free solder rework.
This will provide guidance on the rectifier bridge failures and fixes:
https://www.eevblog.com/forum/repair/siglent-spd3303x-e-reboot-problem/

[orzel]

Easy fix for any capable hobbyist...although the soldering might be challenging for those not experienced in lead free solder rework.
This will provide guidance on the rectifier bridge failures and fixes:
https://www.eevblog.com/forum/repair/siglent-spd3303x-e-reboot-problem/

Ah, indeed, doesn't seem difficult. I might even have a working version despite "3.0" being mentionned in the the about window.

I'm not a real "dave's fan", i haven't opened it yet 

 I haven't even hacked it, i don't have the need for added precision, and it worked so well so far... "if it ain't broken, don't fix it"

[tautech]

I haven't even hacked it, i don't have the need for added precision, and it worked so well so far... "if it ain't broken, don't fix it"

100%

AFAIK Siglent got a bad batch of those tiny 2A circular bridges and then we started having the odd failure so they they changed the PCB layout to accommodate a more robust bridge, 4A IIRC.

[rolfdegen]

I'm back to the old firmware and have no failures. The question remains, why does the output channel in the new firmware turn off the output channel after a while? I tested with load (12V/50mA) on CH2 and tested without load. It switches off on all attempts.

[tautech]

I'm back to the old firmware and have no failures. The question remains, why does the output channel in the new firmware turn off the output channel after a while? I tested with load (12V/50mA) on CH2 and tested without load. It switches off on all attempts.

Just looked back through your posts and only suggestion is the newer FW is placing more demands on the control PCB PSU and its old style rectifier bridge.

In your position I would swap it out for an uprated bridge modification.
The last one I did I drilled and tapped the main heatsink and ran a 4 wire AC/DC loom to it from the front panel PCB.

[rolfdegen]

Hallo electronic friends..
This bridge rectifier 2W06 from SEPRI is installed in my SPD3303X-E. The current temperature in the open housing is 41 °C after half an hour.

Siglent SPD3303X-E Frontpanel


2W06 Datasheet

[rolfdegen]

I have now closed the case. After three hours of operation without load, the bridge rectifier has a temperature of approx. 50°C. No heat points. The temperature is in the green range 

[rolfdegen]

A TL431C ensures good stability.

SPD3303X-E Front PCB


TL431C Datasheet

[Wade2019]

I have an SDP3303D and I use the statement CALibration: VOLTAGE ch1,1,0.8613. The beep of the buzzer does not work. I use the following statement: CALibration: VOLTAGE ch1,1,0.8613 CAL：VOLT ch1,1,0.833   No effect, who can help me?

[BreakingOhmsLaw]

I have an SDP3303D and I use the statement CALibration: VOLTAGE ch1,1,0.8613. The beep of the buzzer does not work.

LXI is case sensitive AFAIK. Maybe it trips on VOLTAGE instead of VOLTage Try:

CALibration:VOLTage ch1,1,0.8613

[Wade2019]

I tested SCPI:

CAL：VOLT ch1,1,0.833     ERROR  The beep of the buzzer
CAL：VOLT ch1,1,0.83311     ERROR  The beep of the buzzer
CALibration：VOLTage ch1,1,0.8613   ERROR  The beep of the buzzer
CALibration：VOLTage ch1,1,0.861   ERROR  The beep of the buzzer

I am using the software NI MAX and my power supply is SPD-3303D    Seeking everyone's help

[SuperD]

This is for anyone getting the beep every time they send the voltage calibration command. I have hardware V3.0, and downgrading to firmware version 1.01.01.02.05 is what fixed this for me. .07R2 doesn't do anything I need, so I am keeping it here.

I had no issues setting 4 decimal positions like below. I think its all firmware related. I guess never trust an "R" or "B" in the firmware number.

With firmware version 1.01.01.02.07R2 it beeps (any number of signs after 0.).
With firmware version 1.01.01.02.05, calibration commands are accepted without errors.

My calibration commands:
CAL:VOLT CH1,1,0.8195
CAL:VOLT CH1,2,25.5040
CAL:VOLT CH2,1,0.8060
CAL:VOLT CH2,2,25.5015

[sy]

For a budget solution I'd rather go for the method of the beefy load resistors suggested by BreakingOhmsLaw, on par with a good ampmeter and voltmeter. As long as you can measure accurately the load current, a resistor would be more stable.

What kind of "beefy" resistors would I be looking at purchasing for testing the DC current?
What wattage it needs to be able to handle? And what tolerances should I be looking at?

[Mortymore]

Worst case scenario: 32V * 3A = 96W, so an 100W resistor will do.

But, but for current calibration one will need to set for 10V and 3A, I believe, so we have, 30W and 3.33Ohm.
3 paralleled 10Ohm resistors will make a 3.33Ohm resistor, and wattage of each can be even lower.

In the safe side I'd use 50W resistors, and would not rely on their accuracy, because a good a multimeter is what's important.
If, for instance, one can't set exactly 2.500A, and 2.432A is what's being measured, then 2.432 is what should be set for calibration.

Hope I'm not disregarding something.

[sy]

Worst case scenario: 32V * 3A = 96W, so an 100W resistor will do.

But, but for current calibration one will need to set for 10V and 3A, I believe, so we have, 30W and 3.33Ohm.
3 paralleled 10Ohm resistors will make a 3.33Ohm resistor, and wattage of each can be even lower.

In the safe side I'd use 50W resistors, and would not rely on their accuracy, because a good a multimeter is what's important.
If, for instance, one can't set exactly 2.500A, and 2.432A is what's being measured, then 2.432 is what should be set for calibration.

Hope I'm not disregarding something.

This is my first time calibrating and I want to make sure I got this right before making a purchase so please correct me if I am wrong.

I'm going based of what you're saying, so if I had like 3 parallel resistors, the worst case would be:
P=32V*1A=32W (per resistor)

Then we add some tolerance to make sure the resistor is not operating at its maximum rating:
So choose something like 50W.

But then to get the resistance value, wouldn't I be instead doing:
R=32V/1A=32Ohms (per resistor)

This resistance would limit the current through each branch of the parallel network, while the wattage remains well above the worst case.

Also I'm not sure what types of resistors would be good. I've had a look at some wire wound ones but I've seen them go for like $20 a piece which is absolutely ridiculous!

And also, when I am testing this current, do I need to hook the load up and keep it running for an hour to stabilise, or is it leaving the power supply on for an hour before connecting the load?

TIA!

Edit:

Taking another look, I've found some of these $7 resistors. Would they be good enough to use for this prupose?
https://au.mouser.com/ProductDetail/YAGEO/AHA50AJB-30R?qs=sGAEpiMZZMtlubZbdhIBIP1s4nuCZf1cZfhdKdBp1aw%3D

[Mortymore]

From OP...

...

Current display:
...
Set PSU channel to 10V, 3A.
Connect to an electronic load and set it to 100mA constant current. Check actual current with multimeter and enter into the command below:
CALibration:CURRent ch1,1,<measured current value> or ch2 for CH2
Change the electronic load to 2.5A constant current. Again, actual current with multimeter and enter into the command below:
CALibration:CURRent ch1,2,<measured current value> or ch2 for CH2
...

From this description, for current calibration you will need to set the PSU for 10v, 3 A (current limit). And you will also need to draw 2.5A.
3 // 10 Ohm = 3.33 Ohm => 10V / 3.33 Ohm = 3A => P = V^2/R = 10^2/3.33 = 30W
2 // 8 Ohm = 4 Ohm => 10V / 4 Ohm = 2.5 A => P = 10^2/4 = 25W
And so on, for any given current you might need for calibration.

I built some dummy loads with power resistors and repurpose old CPU coolers and PSU cases. The one in the image attached has only 2x 8Ohm 100W resistors to load audio amplifiers for testing/repairing/adjusting. With a setup of a few power resistors, several resistance values can be achieved by different resistor associations in series or parallel, and that's handy for many purposes.

I didn't find trivial to calibrate the SPD3303, and only did it fully when I had a 5.5 digit multimeter and an SDL1020 available.
But with care, I think with power resistors as load, and given an hour to set everything, the calibration can be done.
I like the DL24 to test batteries and such... but I wouldn't trust it to calibrate this PSU

EDIT: Maybe this thread about dummy loads could be of interest:
https://www.eevblog.com/forum/beginners/dummy-load-for-bench-power-supply-resistors/