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I recently got a PeakTech 6225A power supply for my hobby of making/"tinkering"/messing around. I get many parts that I want power separately to diagnose them. I also get a lot of electromotors and get asked to see if they work.

Unfortunately, the manual states:

Do not operate the device to power inductive loads, such as electric motors, which act as a generator during overrun and thus can produce a reverse voltage!

I am very inexperienced in electronics, so I chose to ask this specific question, rather than applying concepts from answers to similar questions, as my grasp on the matter is not firm enough yet.

My idea was to make a kind of module/filter that I could plug between the power supply and the electromotor that would protect the former from reverse voltage.

There are several components buzzing in my head: a TVS diode? A MOSFET? RC snubber? Flyback diode? Would a bidge rectifier do anything, since reversing the input polarity isn't an issue, it's the reverse voltage from the inductive load.

Can I apply the circuit described in this blogpost to protect my power supply?

Could I take his (second last) circuit as is, or should I make some adjustments?

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A simple series diode would provide considerable protection from an inductive load. A flyback diode would provide additional protection.

schematic

simulate this circuit – Schematic created using CircuitLab

Edit: the diagram just shows generic 1N4001 diodes. Make sure the ones you use are rated for the current and voltage you require. The 1N4001 isn't suitable for large currents.

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    \$\begingroup\$ At this relatively low voltage, I'd use Schottky diodes. \$\endgroup\$
    – Olin Lathrop
    Sep 24, 2018 at 11:42
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    \$\begingroup\$ 30V @ 5A can turn quite big DC motor. make sure your flyback diode up to the task \$\endgroup\$
    – Maple
    Sep 24, 2018 at 12:10
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At your level, just get a suitable power supply.

You can try connecting a power diode permanently across your power supply in reverse. That shouldn't hurt anything, but it may not help much either.

The real problem is that you bought the wrong supply for your application. The best fix is therefore to get the right one.

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    \$\begingroup\$ That lab supply seems to be good choice for stated goal of "messing around". It's specific load that needs additional treatment \$\endgroup\$
    – Maple
    Sep 24, 2018 at 11:52
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    \$\begingroup\$ I would look at 5A differential Line filters and TVS clamp over voltage diodes to reduce transient commutation kickback pulses along with reverse diode clamps across any passive or active transistor switches to motors in either direction. Added to above along with low ESR bulk caps to load supply. \$\endgroup\$
    – Tony Stewart EE75
    Sep 24, 2018 at 13:34

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