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Nikon Power Supply

Posted: Wed Dec 04, 2019 10:34 pm
by goochlab
We have a Nikon Microphot-FXL microscope with a PSM-4 power supply. For awhile, the power supply would only turn on if we rapidly flipped the power switch on and off quickly. Now it won't turn on at all. Are there universal power supplies we can use to replace the one we have or are power supplies very specific to the microscope? If we found one with the correct volt, watt, etc. can we just replace it? Alternatively, I've seen PSM-4A power supplies but am not sure if this would work since it's a similar but different power supply.

Thanks,

Kevin

Re: Nikon Power Supply

Posted: Wed Dec 04, 2019 10:50 pm
by PeteM
The defect sounds as if it could just be the switch not making proper contact. You might try jumpering around it, if comfortable with wiring. There are usually simple and cheap replacements for most any on-off switch, including fancy ones internal lamps, two poles, and fuses included.

If it's actually the power supply, a modern replacement with the same voltage range and sufficient power (amps, watts) should do. Note than any special power controls cabled from the supply to the scope won't be replicated. You might have to purchase a variable voltage supply and bypass some internal wiring to get more directly to the lamp??

Re: Nikon Power Supply

Posted: Wed Dec 04, 2019 10:55 pm
by Hobbyst46
I have operated both 12V/50W halogen lamps of the Nikon Optiphot with non-Nikon, relatively new general-purpose bench DC variable power supplies; the current needed was about 2.5-3A at most (I think; can double check if of interest). For this to work, on the lower (trans-illumination) lamp, I bypass the internal wiring and switch and display, as suggested by PeteM, and rely on the external power supply as dimmer and display.

Re: Nikon Power Supply

Posted: Thu Dec 05, 2019 4:18 pm
by goochlab
First, thanks so much for the helpful comments. I believe this also supplies other special controls besides the lamp (for instance the digital screen) since the plug connecting to the microscope has over 30 pins in it and there doesn't seem to be other power sources. Image. However, I feel comfortable trying to change the on/off switch. If that works, it should hopefully fix everything.

Thanks again!