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Category — Products

Schneider Altivar ATV31H037M2 VFD

I’ve been playing around with my Schneider (formerly Telemecanique) ATV31H037M2 0.5 HP VFD (variable frequency drive).  I’ve put up some notes here.  Here are my thoughts:

  • If I ever need a VFD at work, I’ll consider Schneider.  Based on a quick look, pricing seemed in-line with comparable VFDs.
  • I think the -A version (with speed control on the front panel) is worth the extra ~$30 since it makes playing around machine setup so make easier.  You can jog the standard version using I/O and switches or via software and Modbus/CANOpen.
  • I really like having CANOpen as a standard interface (Modbus is also standard).  However, the CANOpen setup isn’t ideal, since you’ll have to make a custom cable or use a breakout board.
  • There are a lot of settings; the drive appears to be very flexible.
  • The manuals are very long and thorough.
  • However, the manuals don’t provide much guidance on how to tie all the settings together (so I’m not sure when to use the more advanced settings and how to use the various settings together).
  • Good cable and wire flow.
  • The AC power input and drive connectors do not have permanent labels; but so far the sticky labels are still hanging on.
  • The buttons are cheesy dome switches, which will probably wear out quickly if they are used heavily.
  • The controller’s user interface sucks; to be fair, I’m pretty sure it’s similar to most VFD’s.  If you’re doing a lot of setup, it’s probably worth getting Schneider’s cable and setup software.
  • The newer ATV32 drives are pretty different; for example, the dome switches are gone, and you can get a CANOpen communication card with dual RJ45 connectors.

February 23, 2012   No Comments

Compact (Tenkeyless) Keyboards

My Current Keyboard Setup

My Current Keyboard Setup

As I’ve written before, I find compact keyboards to be more comfortable than normal full size keyboards.  Compact keyboards are also called Tenkeyless keyboards since they do not have the numeric keypad on the right.

I currently have four compact keyboards:

  1. My original, a Lenovo Ultranav scissors switch keyboard with trackpad and trackpoint.
  2. An IBM SpaceSaver M4-1 keyboard with trackpoint.  It was made by Lexmark and has rubber dome key switches.
  3. Two Unicomp Model M Mighty Mouse keyboards and two Unicomp keypads.  These keyboards have rubber dome key switches.

The IBM and Unicomp keyboards are quite similar; for example, I can use the Unicomp keypad with the SpaceSaver keyboard.

My current work setup (shown above) is a Unicomp keyboard and keypad with my Kensington Orbit trackball in the middle.    I like having the keypad for heavy number entry; I like the keypad being out of the way since I don’t use it often.

The SpaceSave and Model M keyboards have a different feel than the UltraNav; they’re more crisp and clicky.  I like both styles (especially the Lenovo keyboard on my laptop), and both are much better than the typical, mushy keyboard.

Sometime I do want to try a mechanical keyboard, probably something with Cherry MX Blue keys such as a Leopard.  I find illuminated keyboards interesting; I’m pretty sure I’d want a tenkeyless one with Cherry MX Blues (unlike the Deck 82 which only comes with Cherry MX Blacks)

Although Unicomp doesn’t make a tenkeyless buckling spring keyboard, I’d still like to try a buckling spring keyboard (probably the EnduraPro).

The best resource on great keyboards is, of course,; for example, check out their mechanical keyboard guide.


January 24, 2012   5 Comments

Review: ActiveMetal Metal Switch

The box

The box

Front View

Front View

Side View

Side View

Back View

Back View

I recently bought an ITW ActiveMetal button because the price was somewhat reasonable, because it uses a unique technology, and because they are no longer readily available after ITW sold the technology to Texzec.

The only distributor with any stock left is Newark; when I ordered mine, they had a total of 5 units available in 3 models.  I bought a T01-042203-006-NO-M2 which breaks down as follows:

  • ActiveMetal button using ultrasonic energy trapped in resonant cavities.
  • Zinc alloy housing.
  • 22mm size
  • 10-24 VDC input, Open collector output.  Since I’m using it with a PLC, I like 24VDC, and the open collector outputs let me use the button with sourcing or sinking inputs.
  • Bright chrome color (I also considered the mirror black color)
  • Normally open switch status
  • Momentary switch action
  • Medium sensitivity level.

The price ($37) is OK for a metal button.  The chrome looks very sharp, but might scratch easily (mine already has a scratch); I would probably pay extra for stainless steel if I were going to use them on a machine.

I won’t make any promises,  but it appears to be ESD-safe; all the exposed metal is grounded together with the black ground wire, although there is noticeable resistance when measuring between various places on the metal surface and the ground wire.

I have the button connected to a Panasonic FP Sigma PLC with PLC inputs configured as sinking (the load provides 24VDC), since I am currently using the PLC with a few PNP-output Pepperl Fuchs inductive sensors.   I have the connected the  button’s red wire to +24VDC, the black wire to ground, and the green wire and a 4.7K Ohm pull-up resistor to the PLC input.

The button does take a little pressure to actuate, so anything that presses hard enough on the button should actuate it (I tried various objects with no problems).  However, because there’s no mechanical feedback, you can’t tell if you’ve successfully pressed it.  I would always use the button with some kind of feedback; currently, I’m using the PLC’s input status LED.

If you need to press a button frequently, the ActiveMetal’s light touch could be an advantage compared to a typical 22mm mechanical pushbutton.  Recently, I was testing out an Allegro UCN5804 stepper driver using my ActiveMetal button to generate the step pulses, and I appreciated its ease of actuation.

In most cases I think I’d rather use a nice illuminated mechanical pushbutton (such as the IDEC LW7L), but if I need the unique advantages of a non-mechanical button (such as better ESD safety, longer life, or greater robustness), I’ll definitely consider ActiveMetal buttons.

November 23, 2011   No Comments

Best Industrial Equipment For The Garage: 2011 Update

Overall my original post on buying surplus industrial automation equipment is still on the mark.  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.  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.  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%.  In general, “Buy It Now” means “I think my junk is worth a lot”.  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.  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.  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).  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).  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).  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.  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).  The Accelnets are my favorite servo drive.  I avoid the older models (800-xxxx)  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.  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.  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).  Opto 22 PACs are rare and expensive, especially the current models.  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

Mouse Alternatives For MCAD

Matt Lombard has a post on his search for a mouse replacement.  I recommend reading it; the post has lots of pictures and good commentary.

I primarily use my computer for software development, browsing, blogging, and such, so my needs are a little different.  I’ve talked about my Kensington Orbit trackball before.

I’m still satisfied with my current desktop setup: IBM Ultranav Thinkpad keyboard and Kensington Orbit trackball; my hand and arm strain is still much reduced, and both input devices work well.

The Ultranav has both a Trackpoint (pointer stick) and trackpad.  I still tend to use the trackball for most pointer moves.  I like the shorter width (less arm movement to get to the trackball), and overall, the feel is good.  However, even though I bought a PS/2 IBM branded Ultranav made by Lenovo, which is supposed to be better than the newer Lenovo USB models, I still find the Thinkpad keyboards to be much better on a Lenovo laptop.  Maybe it’s the extra mass below them; the laptops are >4 lbs, but the standalone keyboard is pretty light.

Sometimes the trackball is awkward, but overall, I’ve adapted pretty well.  I still might get a Kensington Ultimate trackball, since they’re somewhat affordable on eBay, but I’d have to check into the driver situation again (I’ve seen many complaints about their Vista/Win7 drivers), and I’d have to find uses for the extra buttons; in the past, I’ve never used extra buttons.

Although many of Matt’s readers like the Logitech trackballs, I still like the Kensington models better.  Quite a few readers also love the 3D Connexion controllers; sometime I do plan on picking up a Navigator and/or SpacePilot.  Used SpacePilots are available on eBay for reasonable prices, but they’re kind of big; I’d have to be sure I’d use all those extra buttons before I’d buy one.

I still use other setups quite often; I use and like the Lenovo Trackpoints, I often use a Microsoft Bluetooth Notebook Mouse 5000 with my laptop, and I still use mice and trackpads on other computers.

February 25, 2011   No Comments

New Integrated Motors from Faulhaber, Animatics, and Schneider

I just took a look at the specifications for some recent integrated motors; integrated motors combine the motor, drive, and controller in one package.  I’ve used motors from all three companies, but not these particular models.

Faulhaber BX4 Series

The Faulhaber BX4 series are attractive,  compact (22, 32, or 35mm diameter) brushless DC motors with integrated encoders, servo drives, and servo controllers.

  • Versions are available with CANOpen or RS-232 interfaces (I’d use CANOpen, of course).
  • They can be paired with a 22F series gearhead, but unfortunately, no zero backlash gearheads are available, and it doesn’t sound like this will change (which means I won’t be using them any time soon).
  • Versions with separate controller power are available.  This extremely useful feature allows you to turn off motor power (e.g. because of an E-Stop) while still maintaining motor position.

Schneider Electric Motion

Schneider Electric Motion USA (formerly IMS) now has a Ethernet option for their all-in-one MDrives.

  • The MDrives combine a stepper motor and driver, and, on the Motion Control versions, a controller.  Encoders are optional; adding an encoder does not increase the motor length (nice job!).
  • Some models feature their Hybrid Motion technology, which detects stalls, enlarges the stepper’s torque curve, and more.
  • The Ethernet interface supports Modbus/TCP and MCode/TCP (MCode/TCP basically extends the MDrive Motion Control programming model from serial to Ethernet).
  • MDrives are also available with RS-485 and CANOpen interfaces.

Animatics Combitronic

Animatics has a new interface option for their integrated SmartMotors, the Combitronic network with a maximum speed of 1M bit/sec.

  • The Combitronic network uses the CAN bus as its physical layer.
  • It extends the Animatics programming language to the entire Combitronic network; for example, any SmartMotor can easily access any variables on other SmartMotors on the network.
    • So Animatics claims Combitronic allows true distributed processing; you can treat the whole network of SmartMotors as one large multi-axis controller.
    • You should be to do similar things with other networks; for example, use programmable CANOpen nodes (such as Wago 750-838’s) and share variables via PDOs.  However, I am not aware of another implementation that looks as easy to use.
    • On the other hand, I’m not a fan of the Animatics programming language; it quickly becomes very limiting for complex tasks.
  • Another nice feature is that the Combitronic network “plays nicely” with other CAN based network; since it will not interfere with CANOpen or DeviceNet traffic, you can mix Combitronic devices on the same CAN network with CANOpen or DeviceNet devices.
  • SmartMotors are also available with RS-232, CANOpen, DeviceNet, Profibus, and Ethernet TCP/IP interfaces.
  • Now you can get SmartMotors with separate controller power.  As I noted above, this is a great feature.  I have a SmartMotor application using older models without separate power, and it sucks (the SmartMotor has to be re-homed after every Light Curtain interruption or E-Stop).

I do think Animatics overstates their advantages; however, they are a good fit for the right application.  For example, I once did a X-Y table with two SmartMotors, controlled by a sweet CH Products analog joystick.  The joystick’s analog output was fed directly to the SmartMotors, so there was no controller (PC or PLC) required.

Final Thoughts

Although integrated motors are cool, in many applications a regular motor is a better fit.  The combination of a standard motor and a network drive (amplifier + controller) is almost as easy to wire, often less expensive, and much more flexible.

If I have a choice, I will use an integrated motor with a standard fieldbus (such as CANOpen) over a programmable model — motor manufacturers simply do not know how to create decent programming languages.  I have programmed both MDrives and SmartMotors; the experience is like a trip back to 1977 and TRS-80’s.

I find it interesting that neither manufacturer supporting Ethernet uses a real time protocol such as Powerlink, EtherCAT, or Profinet-IRT.

the Animatics programming language to a network of devices.

January 20, 2011   No Comments

Panasonic FP0-R PLC Surprises

Recently, I used my first Panasonic FP0-R PLC in a machine (as a drop in replacement for a FP0). Even though I’ve read the FP0-R specifications, I did have a couple surprises along my journey to a working machine.

The not so good surprises:

  • You need the FPWin Pro V6.0 or newer development software to initially download to the FP0-R.  Pretty frustrating, since I only had FPWinPro V5.3.
  • OK, Panasonic also offers FPWinGR, but I’ll never consider it, because FPWinPro implements the IEC-61131 programming standard (yeah, structured text! ) and when I first tried FPWinGR, about a decade ago, it was, to put it nicely, a putrid steaming pile of crap (OK, I’ve seen worse, but it wasn’t very good then).
  • Of course, getting a new, full versions of these (FPWinPro or FPWinGR) costs money.
  • The free program loader program I was using, PLC UpDown V2.55, doesn’t work with the FP0-R, and I can’t find a newer version.  FP UpDown let me upload the memory of the PLC into a NSU file and then download that NSU file into another PLC.
  • Panasonic does have a free loader program, FPLoader, that does work with the FP0-R, but it only downaloads FPWinGR programs (not FPWinPro), and can’t upload.

But I was pleasantly surprised, because:

  • Panasonic has a free FPWinPro version, FPWinPro 6.2 basic, that is only limited by the maximum program size, which varies depending on the PLC model; it’s 2.7K/300 steps for the FP0/FP0-R and 12K/500 steps for the FP Sigma.  My current programs are all smaller than that, so thank you, Panasonic!
  • The FP0-R has compatibility modes that let it mimic FP0 PLCs such as the FP0-C32 and FP0-T32.  When the FP0-R is in compatibility mode, you can use FPWinPro 5 (or FP UpDown).  I found trying to switch between native and compatibility modes a little unpredictable.
  • So you can still download a large FP0 program without upgrading to FPWinPro V6 by first using V6.2 basic to set compatibility mode, and then using the older software to download the big program.
  • The second serial port is now much faster, with a maximum speed of 115200 bps, while the FP0’s topped out at 19200 bps.
  • The USB tool port worked smoothly.

January 15, 2011   No Comments

A Less Expensive Magnetic Linear Encoder

I haven’t found the linear encoder promised land I was looking for, but recently I did learn a bit about some reasonably priced linear encoders: Turck’s LI20 and LI50 hall effect based magnetic linear encoders.

The LI20 is available with 10 micron resolution, and handles speeds up to 25 m/sec.  The LI50 is available with 5 micron resolution and speeds up to 16.25 m/sec (although at 5 microns, max speed is about 3 m/sec).

If I have my part numbers and PLC Center pricing correct, a T8.LI20.1111.2050 with 1 meter encoder strip (magnetic band) would be about $315, and a T8.I.LI50.1111.2250 with a 1 meter encoder strip would be about $430.  (For the magnetic band, I’m assuming buying 90 m (T8.B1.10.010.0900 or T8.B2.10.010.0900) and cutting into 90 pieces each 1 m long; it looks buying shorter lengths is considerably more expensive per meter).

Note 5/10/2010: Honeywell also makes affordable magnetorestrictive linear encoders, although I don’t think they are well suited for typical industrial automation applications.  Minimum resolution is 140 microns, length is 75 or 225 mm, and output is analog or RS-232 (225mm only).  The SPS-L225-HALS (225mm analog) is about $250.

November 13, 2010   No Comments

Mouse Alternatives

A while ago, I did way too much mousing (setting up vision jobs with Cognex Insight) and ended up with significant shoulder strain.  I’ve been better since (but not back to normal), partly by watching how much mousing around I do.

Recently, I decided it was time for another approach, and bought a Kensington Orbit Trackball with Scroll Ring.  Overall, it’s working pretty well; I’ve been using it for less than a  week, and my arm and shoulder definitely feel better.  The scroll ring works pretty well (I’d say better than a typical mouse wheel).  The ball is pretty big (about 1.5″), and is very smooth.

I also went to a smaller keyboard; I think part of the problem may have been extending my arm too far to get to the mouse.  When I use the narrower keyboard, I don’t have to extend as far.  I was able to scrounge up an old PS/2 mini-keyboard with trackpad.  The keyboard is OK, with a usable layout, but the trackpad is pretty bad (it doesn’t feel good, and it takes a lot of motion to get across my monitor).  Also, I’ve been adjusting my chair height to find the best position.

I’ve used mini keyboards with trackballs in the past, and haven’t been happy with them, because they had mechanical mini-trackballs that took a lot of motion to get anywhere, picked up lint like crazy, and basically were a pain to use.  In the future, I might try a mini keyboard with trackpad if I can test it first (some trackpads are decent), the old Lenovo Thinkpad keyboard (with pointer stick and trackpad) or the new Lenovo Thinkpad keyboard (with pointer stick only, but more affordable price).

I looked at some Logitech trackballs; I went with the Kensington because the ball seemed substantially larger, I liked the the scroll ring, and I’ve tried some Logitech trackballs in the past and wasn’t impressed (I do like their mice).  I wouldn’t mind having a larger ball and more buttons, but I’m not willing to pay for a Kensington Ultimate (~$90) or CH Products with 2.25″ ball (~$230; I’ve used CH Products joysticks in the past — they are really nice).

August 5, 2010   2 Comments

USB Digital to Analog Converters with Timed Outputs

Recently, I had what seemed like a simple task: select a DAC (digital to analog converter).  There are hundreds of models, so it should be easy, especially since most of my requirements were not demanding (1 channel, 12-bit or better, 1KHz output rate, 0-10V, low jitter output, and reasonable cost, hopefully <$500).   Even my low jitter requirement wasn’t demanding; I’d be happy with 100 microseconds of jitter; basically, any unit with a decent FIFO buffer and a hardware timed DAC update should work.

But finding candidates was a lot of work.  Early on, I concentrated on USB DAC models, because they have sufficient speed, are self-powered, tend to be reasonably priced, and don’t need a PCI or PCIe slot.

I’ve used Measurement Computing before, so they were one of my first stops.  It was really hard to find exactly which models have FIFO buffers and hardware paced outputs.  I had to do a lot of searching — and reading the full manuals.

The cheapest Measurement Computing model that met my requirements is the USB-1208HS-2AO, which is overkill ($599, high speed USB 2.0, 2 12-bit analog outputs at 1MHz, DAC has 4K FIFO buffer).  As far as I can tell, nothing cheaper has a FIFO buffer for the DAC.

Data Translation wasn’t much better; I had to dig through the detailed specs PDF to discover that the DT9812-10V meets my requirements, and has a 2K FIFO buffer.  It’s $375; DIN Rail mounting is an extra $60.

The final contestant is the Accesio USB-DA-12-8A, which has a 128K samples buffer.  It’s $525; DIN Rail mounting is an extra $19.

For my application, the Accesio looks the best fit; it more than meets all my requirements, I like the large buffer, andI like the DIN Rail mounting option.

Update Aug 2014:I was look at USB DAQ devices again, and I’m happy to say the situation is much better now.  For example, MCC’s USB-231 for $249 has 2 16-bit DACs that support simultaneous hardware-paced updates at up to 5KHz.  It also features 8 SE (or 4 DE) 16-bit analog input channels with 50KHz max sampling rate, 8 digital I/O, and 1 32-bit counter / timer.

February 11, 2010   No Comments