B+K Precision TR-110 ISOPACK Variable Voltage Isolation Transformer - Page 1
Forum section: electronics / general

author: requim
author_rank: Regular Contributor
timestamp: December 07, 2011, 07:02:41 am
content: I have a used B+K Precision TR-110 ISOPACK variable voltage isolation transformer for sale. The model was discontinued earlier this year. This unit was pulled from a defunct manufacturing facility and is in working order.The unit does have a couple of dents one near the fuse and another on the back. The unit was recently pulled out of long term storage and has/had some minor rusting on the exterior screws. The case seems to have escaped intact. The unit is supposed to range from 90 - 140 volts however in testing I found it ranged from approximately 96V - 143V. I can post some pictures if desired and I can take interior shots if desired as well.More information can be found at the following link:http://www.bkprecision.com/products/model/TR110/isolation-transformer.htmlSend me a PM if interested.I am asking $80.00 shipped via USPS Priority Mail Flat Rate Medium Box to the USA.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: December 07, 2011, 07:26:45 am
content: Im not looking to buy it but internal pictures are always welcome

author: saturation
author_rank: Super Contributor
timestamp: December 07, 2011, 12:54:15 pm
content: I'm interested if you can post photos of the issues you describe, I think others would like to see the guts too, so I'm not PMing you, yet. Thanks for making it available. I noticed it on eBay too.

author: requim
author_rank: Regular Contributor
timestamp: December 07, 2011, 03:49:53 pm
content: I've attached the photos to this post. The photos don't show as clearly as I would have hoped the dent / bend on the backside of the case. The case sits flat on it's back without issue, however if you look at the photo where the line runs vertical, that portion of the frame is bent outwards slightly.I've posted large photos so hopefully you can see what I'm talking about without much issue. If you would like more photos of anything specifically please let me know or if you'd like to see high resolution photos I can post those to my flickr account. Just let me know.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: December 08, 2011, 09:04:26 am
content: Thanks for sharing

author: requim
author_rank: Regular Contributor
timestamp: December 08, 2011, 09:30:33 am
content: You bet. Not much to it really. Massive transformer with wires coming out of it at different points in the winding which allows it to do variable voltage. I was a little surprised by their use of standard power jacks. Not that there's anything wrong with it, just unusual.

author: hacklordsniper
author_rank: Frequent Contributor
timestamp: December 08, 2011, 10:15:09 am
content: Quote from: requim on December 08, 2011, 09:30:33 amThats true because its not easy acessible for test leads

author: saturation
author_rank: Super Contributor
timestamp: December 08, 2011, 04:02:49 pm
content: Thanks requiem, the photos say a lot. It appears decent but it has a lot of heavy competition from other similarly working items on the eBay. The build quality seems more 1990s than 2000+, many leads with potential main voltages on it are not shrink wrapped, not an issue just a clue to its age.

author: requim
author_rank: Regular Contributor
timestamp: December 08, 2011, 04:21:07 pm
content: Yes, definitely 90's era construction. Just so you know I'm open to reasonable offers. In addition I am sending this via Priority Mail which means delivery time in 2-3 days as opposed to ground service which is what most (all?) other units are listed.Also, I do not have this listed on eBay. There is another unit listed on eBay for parts/repair by a different vendor for about $5.00 more than I'm offering this unit.Anyway I thought I'd make the item available here in the forums first before I listed it on eBay. I also figured my listing is more open in the sense that I am disclosing much more info than people usually disclose (interior photos and DMM readings) when selling items. I acquired the unit when I purchased several other items recently but decided to sell it since I already have a premium isolation transformer. Unfortunately for me I will lose money selling this unit. C'est la vie.

author: ivan747
author_rank: Super Contributor
timestamp: December 16, 2011, 10:24:48 pm
content: How much does it weight?

author: requim
author_rank: Regular Contributor
timestamp: December 16, 2011, 11:51:16 pm
content: 15.95 lbs unpacked. And I guarantee you virtually all of that weight is the transformer.

author: ivan747
author_rank: Super Contributor
timestamp: December 17, 2011, 12:22:15 am
content: Weird. I found the datasheet a few minutes ago by accident and BK says this weights 12 pounds. I'll contact a courier company and ask the price for importing something like this. I'll give them a call tomorrow.

author: requim
author_rank: Regular Contributor
timestamp: December 17, 2011, 01:20:35 am
content: I suppose it's possible that on later revisions they were able to reduce the size/weight of the transformer. If I were a betting man I'd say this unit was made no earlier than the 1990's.

author: IanB
author_rank: Super Contributor
timestamp: December 17, 2011, 02:03:01 am
content: Quote from: saturation on December 08, 2011, 04:02:49 pmWhy should the leads be shrink wrapped, actually? They are inside a closed case and are insulated and securely soldered. Shrink wrap isn't going to help much if a connection comes loose.I actually prefer construction from the 1930's or so, before people went stupidly crazy over "safety". If something was safe then, why isn't it safe now? It's the same universe with the same laws of physics. OK, I jest slightly, but it is important that people take personal responsibility for their own safety and not rely on others to protect them. I'm sure kids these days grow up believing anything they do and anything they touch is guaranteed not to harm them, so they can do anything they like without a care.

author: requim
author_rank: Regular Contributor
timestamp: December 17, 2011, 02:05:41 am
content: I agree in many ways. In this particular instance the unit is safe from the standpoint of the user. It may be considered less safe from the standpoint of a technician, but I think we'd all agree that a technician should be aware of the dangers that lurk inside. That's not to say that they do. I know I certainly am still learning, but I know not to touch things when they're powered on and I know to stay as far away from high voltage stuff as possible.

author: saturation
author_rank: Super Contributor
timestamp: December 17, 2011, 02:35:26 pm
content: Its an IPC assembly standard ~ late 1990s, so you can estimate construction date by looking at assembly methods. Those standards grew out of military and aerospace assembly techniques, which are of the highest quality. Wraps are just one part of the requirements, and it isn't just about safety, it also includes reliability and levels of robustness.I'm all for personal responsibility. But safety has to be built in by builders as the technology gets more complex, its difficult for users to know what constitutes safe operation.Taking us back to the topic of isolation transformers, in the 1930s, a hot chassis was a common practice and hardly safe. If a knob cover broke or if the outer case cracked exposing the inner metal chassis, users were exposed to mains voltage fairly easily. Well, if they die that's their fault, they should have paid attention in school.Quote from: IanB on December 17, 2011, 02:03:01 am

author: requim
author_rank: Regular Contributor
timestamp: January 05, 2012, 07:27:24 pm
content: Sold.