Hi

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There is a post on the FaceBook group ?that suggests that if there is a short on the DC output side, the DR60710 power supply cannot handle this because it does not have a built in circuit breaker. As a result of the short the DR60710 is damaged internally and starts sending high voltage to the controllers it is providing power to (controllers = DR5000 / YD7001 command station, DR5033 boosters, etc).? We may be interpreting the post incorrectly, so a translated version of it follows:

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“Just another warning in relation to the old Digikeijs ADJ Power Supplies...

Translation of?'s message using Deepl:

On the photo you can see what can happen if these Digikeijs ADJ power supplies continue to be used without an additional 3.5A fuse in the DC line using the example of a YD7001. As we should know, this power supply outputs up to 33V if the voltage selector switch has a loose contact. This happens more often the older these things get. At this moment, the protective diodes that are supposed to prevent worse things from happening are destroyed. But now comes the second major fault of these power supply units, because they continue to fire 7 to 9 A at the poor YD7001. As we also know, the power supply units have no short-circuit protection. The end result is a charred board, melted housing halves, a soldered DC connection and detached conductor tracks. A fuse may not prevent the initial destruction of the diodes, but it will at least prevent this immense damage caused by charring! So consider carefully whether it is not time to replace the power supply units with safer versions!”

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There is also a video: https://www.youtube.com/watch?v=xYV-M2JXvk0

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Based on this we have questions that hopefully someone in this group can comment on:

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1. Has anyone seen this problem ?? If yes, what was the source of the short on the DC side ?
2. How do we tell if we have an old power supply -? all 10 of them are DR60710s ??
3. Has anyone implemented a 3.5A fuse in the DC line to prevent problems ?
4. Does the DR60710-M, which I assume is a newer power supply, address the problem of a short on the DC output side ?
5. What other power supplies are people using the the DR5000, YD7001, etc ?

Any information you can provide will be appreciated.

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Jay Lennox

Toronto, Canada

Hi Jay,

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Can the DR60710 power supply cause damage to controllers it provides power to ?

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Oh YES it can !

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Look....

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But first:

It CAN be Short on the DC side, must most likely it's the Voltage-Selector slider that malfunctions or any of the internal capacitors get bust. Mostly the PSU then outputs 33VDC :O Then the equipment's safety crow-vbar kicks in. That however can "only" take 5 Amps. Then comes the second flwa into play: The PSU keeps on pushing current until it starts burning a) itsself, b) the equipments crowbar...?

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1. Has anyone seen this problem ?? If yes, what was the source of the short on the DC side ?
   
   Oh yes, more than I like. Even in the time I still did design work for them, I saw an Eployee destroying 5pcs YD5052 (brand new!! ) with a faulty PSU which ouput 26V ...
   
   
2. How do we tell if we have an old power supply -? all 10 of them are DR60710s ??
   
   All of the ADJ types, the ones with the voltage selector
   
   
3. Has anyone implemented a 3.5A fuse in the DC line to prevent problems ?
   
   IMHO that is only curing the symptom.
   
   
4. Does the DR60710-M, which I assume is a newer power supply, address the problem of a short on the DC output side ?
   
   Same el-cheapo PSU with voltage selector, just that the China-Man put an Digikeijs Label on it.
   
   
5. What other power supplies are people using the the DR5000, YD7001, etc ?
   
   Many use this dangerous PSU. We advise our YD7460 PSUs, but also Meanwell GSM60Axx-P1J series is a good choice.

On Thu, Dec 5, 2024 at 06:38 AM, karst.drenth wrote:

GSM60Axx-P1J series is a good choice.

Correction, it is the GSM60Bxx-P1J series

Yes. xx means 15 or 18 Volts.

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AFAIK that are the only suitable versions in the series.

On Thu, Dec 5, 2024 at 08:10 AM, Dennis Cherry wrote:

Attached is the Meanwell Data

But that is for the incorrect "A" version ;)

When Karst recommended the GSMA, I immediately bought 2 of them and I never saw the updated recommendation to use the GSMB. I assume the GSMA is "good enough" or is it worth spending the $ for the GSMB?

On Fri, Dec 6, 2024 at 06:13 AM, Robert Gamble wrote:

the only difference I can see is that the A has a three prong power cord input whereas the B uses a two prong input.

Yep, just cut off the plug to disconnect the PE wire. That's the difference.

Greets,
Karst

Thanks all! Happy Holidays?

Reading all this I can only say I'm glad I ditched nearly all the digikeijs smpsu. I got fed up with high touch voltages to earth on my rails. Go on, try it, put a high impedance meter between your track and an earthed item nearby. Lots of volts to earth. No real current potential, but you can feel it.

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I no longer get shocks from the track to earth. There is no measurable voltage to earth due to the tranformer isolation.

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Karst makes a good point about crowbar protection, and "back in the day" the crowbar protection was a large SCR triggered into conduction on over voltage and used to either hold the PSU output voltage down to the SCR voltage drop, or it would blow the output fuse disconnecting the output from the equipment. It "crowbarred" the supply to an off state. Brutal but efficient.

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The only Digikeijs supply I have left is..... DR60710 ! I aquired it when I bought a secondhand DR5000 (now a YD7001). The DR60710 will be in the bin by the end of today!

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I do find myself questioning the advice to cut the earth lead. If I was at work PAT testing and found such a thing there would be condemned equipment and a written report to my boss. YMMV.

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Pete S. (Industrial Sparkie)

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On Fri, Dec 6, 2024 at 06:21 AM, karst.drenth wrote:

Yep, just cut off the plug to disconnect the PE wire. That's the difference

I wouldn't do that unless the power supply is marked as double insulated class II unit, then it will usually have a 2 pin connector. Power supplies often have filters that are grounded, if you cut the earth wire then any leakage could end up on the output as class I supplies (the GSM60A is listed as such) can have the output connected to the incoming earth. Do a continuity test between the incoming earth and the output wires, if below many megohms this is potentially dangerous.

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I agree with Pete S. I too would have to reject it on a PAT.

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Mike Ruby

Our club is in Toronto Canada and we will be replacing all of our Digikeijs booster and command station power supplies. ? I assume that thee 3 prong version, GSM60A, is the better choice for us since North American AC outlets have a ground wire.????

Is this correct?

Andris

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The only additional comments that I will make on this topic is that Karst, in one of the previous posts, corrected his suggestion that we use the GSM60A supplies and instead stated that we should use the GSM60B supplies.? I cannot recall the reason for the change, but it should be somewhere in this topic.

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Jay Lennox - Toronto