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Matsusada Power Supply Cable

Posted: Thu Dec 28, 2017 12:36 am
by Tom McCarthy
Great news, I just scored a suitable power supply on eBay, "in working condition," $100 plus shipping to Ireland of about $50.

It's a Matsusada WA6-30N. 600W, 30kV, 20mA variable, continuous operation. I would have liked to get something with higher voltage, but I'm not complaining. I've now got my vacuum system working, have my deuterium, flow meter, orifice and valve and need to calibrate the 3He system I'm using with a known neutron source. Other things to do are all related to the high voltage setup - HV cabling, ballast if needed, measurement and testing.

The power supply has been sold without a HV cable. Andrew Seltzman had a look at the pics (attached) and said it looks like "one of those modified RG8 cables with a banana plug on the end." After some searching, I can't find a good reference for this, perhaps it'll be in the manual. Does anyone have a thread that details something similar? Other threads, for Spellman supplies mention PL-259 connections, but I don't think they're applicable.

Also, can anybody find a manual for these supplies? I haven't been able to find one via Google yet, and am waiting to hear back from the seller and Matsusada if they can provide one.
Dimensions, Datasheet

Re: Matsusada Power Supply Cable

Posted: Thu Dec 28, 2017 2:47 am
by Dan Knapp
You can easily make this type of cable yourself from some RG-8 coax and a PL-259 plug. First attach a banana plug to a metal rod and stick it into the receptacle to measure the needed insertion length. Drill out the center conductor and insulation from the PL-259 plug. Strip enough outside insulation and shield from the coax to give you the needed length of coax dielectric/center conductor to give you the needed insertion length with the banana plug attached, then attach the drilled out PL-259. I think the specific instructions for making these cables are in one of the support documents posted on the Spellman web site.
In looking more closely at your photo of the power supply, the connector doesn’t look like a PL-259 (doesn’t appear to have the “saw teeth” of this type of connector). The panel connector may be an N-type. Regardless, you just need the mating male plug that you drill out to make the cable.

Re: Matsusada Power Supply Cable

Posted: Thu Dec 28, 2017 4:15 am
by ian_krase
Best to use RG-213, IMO. It's higher quality and more likely to have solid (i.e. not foam) dielectric.

In case you didn't figure it out, the big advantage of these coaxial HV cables is that if the insulation fails, arcs lead harmlessly to ground.

Also, that's definitely a drilled PL-259 (actually a SO-259, the plug and socket have different numbers). I can see the saw teeth when zoomed in.

ALso beware that the tip connector might be something other than a banana plug.

Re: Matsusada Power Supply Cable

Posted: Thu Dec 28, 2017 11:31 am
by Roberto Ferrari
Am I wrong or the posted specs (highlighted item) has the wrong polarity?

Re: Matsusada Power Supply Cable

Posted: Thu Dec 28, 2017 11:45 pm
by Rex Allers
On polarity, he said the PN is WA6-30N, with the N implying negative, so OK. (30P would be positive.)

As mentioned, making a HV cable should probably not be too difficult. I think the bigger problem is learning what the signals and controls are on the 25-pin connector. Maybe there is a label somewhere I can't see in the picture, or possibly it is a clone of some other supply (Spellman ?). I think that pin information will be critical to using the supply.

Re: Matsusada Power Supply Cable

Posted: Sat Dec 30, 2017 4:28 pm
by Tom McCarthy
Thanks for the helpful responses guys.

I'm still waiting to hear from Matsusada regarding a manual and haven't been able to find information elsewhere. The seller doesn't have a hard or soft manual himself. He did say that the Matsusada HV output cables typically have a different termination style to Spellman. Instead of the banana style termination, Matsusada use a "flat button looking contact." The rest of the procedure should be the same for getting a cable working though, right? Just going to have to find a proper end element.

Rex, there are some details in the images I attached to the post - which pins for readouts and an interlock, but you're right, I'll need more information.

Yes, the item is a WA6-30N, negative polarity. The stars in the spec sheets denote that the model can be either 'P' or 'N' for positive or negative. There's a label on top of the supply that confirms it's WA6-30N.


Re: Matsusada Power Supply Cable

Posted: Sat Dec 30, 2017 4:33 pm
by Silviu Tamasdan
Quick idea about the HV connector, if you have or can borrow one of those endoscope-like devices (used to inspect pipes from inside and whatnot) you could take a look inside the connector and see what kind of contact it has.

Re: Matsusada Power Supply Cable

Posted: Sat Dec 30, 2017 5:56 pm
by Tom McCarthy
Nice idea, I'll check that out if necessary.

More info on the connector from seller:

"I am 99% sure that it’s not a banana and certainly not a smaller Spellman style. If I had to liken it to a particular style it would be close to a hi-trek button but more of a soldered machined piece that actually inserts into a female socket within the power supply but not quite like a banana.

In the past I had to buy these cables from Matsusada and then made my own subsequent cables by machining parts and soldering that to my our hv cable."

I've also checked with Matsusada for a quote on a HV cable from them.

Re: Matsusada Power Supply Cable

Posted: Sun Dec 31, 2017 1:14 am
by Rex Allers
Tom, I've looked again and still see no mention of any pin numbers on the 25-pin I/O connector. There are a few words about some of the functions but no associated pins. Am I missing something?

The description of the connection on the HV cable sounds like the way Glassman supplies do it. They have just a flat metal disc or blob on the end of the cable to make contact inside. In the supply there is a plastic tube to guide the several inches stripped cable that projects inside. At the far end of the tube is a spring with a metal disk as the contact.

I've made a couple cables for Glassman supplies. To get the length inside to the contact, I put a wooden dowel into the HV connector. Pushing gently you can feel when it makes contact, then pushing a little harder you can feel the spring compress. So I made the length the distance from the outside end of the connector to the first contact, plus about 1/2 inch to compress the spring.

Here's a picture of one 60 KV Glassman supply module.
60KV HV unit.jpg
The left end of the white plastic tube goes into the panel screw connector. If you look closely near the center of the tube (below the white screw head) you should be able to see the spring inside. To the right of this spring are some series resistors for a bit of protection.

Maybe this description will work for making a cable. The earlier descriptions of drilling out a PL-259 apply here too.

Re: Matsusada Power Supply Cable

Posted: Sun Dec 31, 2017 1:32 pm
by Tom McCarthy
Ok, thanks Rex, that’s very useful info. I’ll check if the connection has a spring when it arrives.

Also, you’re right, there aren’t any I/O pin numbers on the page, laziness on my part, I just remembered seeing the function descriptions.