Vision Engineering Mantis supply voltage

[1design]

Hello everyone,

I managed to get my hands on a Vision Mantis, the issue I am facing is that it is a 110V AC 60Hz unit and I need to change this to 220V AC 50Hz. Changing the transformer is not a problem, the issue is that there is no info about the secondary voltage on the current transformer. From the halogen lamps I would say it has 12V secondary voltage, could anyone that owns one check what is the voltage on the jack that goes from the stand into the microscope head? Thanks!

I almost forgot, it's the original version, not the new one!

Regards,
Miha

[1design]

No one has one at home or at work?

[DenzilPenberthy]

Mine is 9v centre positive.

[DenzilPenberthy]

Presumably mine is a new one? I bought it about 2 months ago. What's the difference between the two?

[DenzilPenberthy]

OK, third time lucky at actually reading your post and absorbing all of the information 

Presumably the difference is that mine had LEDs and yours has halogens.

[Precipice]

Mine is ancient, with the little Halogens. (in fact, the original little halogens!)
12.54VAC (UNLOADED!), no DC component. I guess the annoying buzzy thing in the stand is just a transformer.

[SeanB]

Those 35mm halogen lamps are surprisingly expensive when bought as a microscope light, but buy them as downlighter lamps the price is a little better.

[1design]

Thank you very much for this piece of useful information, so my assumption was correct that they use a 12V transformer.

Regards.

[SeanB]

For an incandescent lamp a simple 50/60Hz transformer would be all you need.

Just be careful as sometimes those transformers are not isolated, just being autotransformers with a 120/220V winding with a 12V tap, saving on a winding and a few grams of copper wire. This is fine so long as the lamp is totally enclosed and with no way to touch the internal wiring at all without unplugging it and removing covers, but just something to be aware of if replacing it.

[rolycat]

If you own an original Mantis, I would recommend replacing the halogen lamps with a couple of ~2W MR11 GU4 cool white LED lamps with a 30 degree beam angle. You can then remove the blue filter glasses and disconnect that annoying fan.

[Precipice]

I will, just as soon as LED lamps get a spectrum that doesn't look weird.
The reason I love my Mantis so much is that it doesn't lie, doesn't lag, generally doesn't piss me off. (except for the rattling transformer, which is far louder than the fan, on mine).
I figure these lamps have lasted me almost 20 years, I can afford to wait a while more before swapping them out...

[1design]

I have already ordered a new toroidal transformer, so no rattling on this one. The original was a EI core with isolated primary and secondary winding. If yours is emitting a hum and it is disturbing you it is quite a strait forward procedure to replace it

BR

[SeanB]

Humming EI cores can often be helped by undoing the bolts and realingning the plates then retighten them after a coat of varnish is applied. This binds the loose plates together so they no longer vibrate.

[OSU_Matthew]

If you own an original Mantis, I would recommend replacing the halogen lamps with a couple of ~2W MR11 GU4 cool white LED lamps with a 30 degree beam angle. You can then remove the blue filter glasses and disconnect that annoying fan.

Hey, you're awesome, thank you so much for posting this, I've been scrounging for scraps of information trying to figure out what kind of bulbs this thing takes. The manual is pretty sparse when it comes to any useful information.