Posts from — June 2011
Overall my original post on buying surplus industrial automation equipment is still on the mark.Â I won’t repeat it again this year; instead, here are some comments based on 3 years of monitoring eBay and adding to my collection.
In Silicon Valley there are only two decent electronic surplus stores: Excess Solutions and Advanced Component Electronics.Â There hasn’t been a good local source for mechanical surplus since Triangle Research closed its doors.
On the web, PLCCenter has a great selection, is great for getting an idea of what stuff costs new, but has premium pricing (except for some on-sale items).
eBay is still the best source, but you need to be patient and know what equipment is worth.Â In general, I’m willing to pay 10-20% of the original cost, but many eBay sellers try to get 50%, and a few even ask for more than 100%.Â In general, “Buy It Now” means “I think my junk is worth a lot”.Â Availability is very spotty; some months there’s a lot of interesting stuff, some months there is nothing.
Also, be sure to check condition and return policies.Â Many eBay sellers do not have the ability, equipment, or inclination to test industrial equipment, so if it says “as-is”, don’t pay a lot.Â Most of the industrial equipment I’ve bought has worked, but I’ve bought a number of AMC and Elmo drives that don’t want to communicate (since the lights blink, I haven’t given up yet; I haven’t had time for extensive troubleshooting).
Don’t forget new equipment; many vendors (including Siemens and Panasonic) have offered somewhat-affordable starter packages including equipment and software (e.g. PLC and programming software).Â Some new PLCs are so inexpensive you don’t even need a starter kit: for example, Automation Direct’s Click PLC starts at $69 and the software is free.
Comments on specific equipment:
- Last time I checked, it appears the Cognex Insight smart camera software is now a free download (after registration).Â But I recommend verifying this before buying an Insight camera (which will probably cost >$100).
- DVT smart cameras are still often available on eBay, with pricing ranging from $50 (Legend 510 bought at the right time) to $500 or more (color model such as the 542C).
- Galil motion controllers availability is good, with a wide range of pricing (there are many unrealistic sellers).Â USB and Ethernet models are more expensive, although if you’re lucky you can buy one for under $250.
- CANOpen interfaces from Kvaser and Ixxat are frequently available for $50-$150.Â I’d recommend getting a used Kvaser or Ixxat instead of a new interface from someone else (which will be at least $100 anyway) because they have the best software support.
- Copley CANOpen servo drives are available fairly often; a reasonable price for an Accelnet is $50-$120; the Xenus is more expensive (>$150).Â The Accelnets are my favorite servo drive.Â I avoid the older models (800-xxxx)Â because I can’t find any documentation for them.
- Elmo CANOpen servo drives are frequently available.
- Ethernet Powerlink drives and EtherCAT drives are occasionally available , but the prices typically aren’t reasonable.
- MEI controllers are often available, at a wide price range, but I’ve never seen the software included.Â If you don’t have MEI software, don’t buy the board.
- Panasonic PLC’s are frequently available, but in general I think the asking prices are too high.Â At least Panasonic now provides a code-sized limited (but still quite useful) free version of FPWin Pro 6.
- Opto 22 I/O controllers, such as the B3000 and LCSX, are frequently available, often at reasonable prices ($50 and up).Â Opto 22 PACs are rare and expensive, especially the current models.Â Opto 22 I/O module availability is good.
- Wago 750 and Beckhoff K-bus availability is good, and, if you’re patient, you can get them at a reasonable price.
- The most popular couplers are for DeviceNet, CANOpen ($25-$75), Profibus, and Ethernet (>$100 for 750-842); I’ve also seen Interbus, serial, and EtherCAT.
- Digital input and output modules are the most common, and cheapest.
- Analog modules are less common, and more expensive, but if you’re patient, you can get one for <$50.
- Specialty modules, such as encoder interfaces and stepper drivers, are the least common and most expensive.
June 20, 2011 5 Comments