# Anyone know where online to get a 2-10vdc 4-20ma generator



## Nephi (Mar 20, 2010)

maintenence men at the black top plant Im at have one but I had actually never even seen one until last week. Ill ask tomorrow where they got it and if its for sale


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## mattsilkwood (Sep 21, 2008)

What model fluke for $400?


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## Matt (Feb 3, 2008)

mattsilkwood said:


> What model fluke for $400?


I am wrong the fluke only test the 4-20mA signal and it is $500.00
it doesn't even generate a signal.
I picked up a 24vac to dc inverter today that has an adjustable pot on it but I will still need to power that with a transformer.
The GE start up tech that came to start the VFD's had a nice battery powered digital signal generator but I did not get a chance to find out what kind it was.


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## mattsilkwood (Sep 21, 2008)

I believe the fluke 789 (model#?) is what you are after. It is a 4-20mA source. It's also quite a bit higher than 400 bucks.


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## miller_elex (Jan 25, 2008)

I believe you can use a 10vdc source, rectify the 24vac and use a voltage divider with a 10V zener diode to get the 10Vdc, then come off that with a 20kohm Pot, and the wiper will have your 0-10V. Put in a couple test points to jam your meter probes in to verify voltage while yur strokin. You could even put some test points in series, in parallel with a switch, put the meter in milliamps and put the leads in the test point, open the switch, and now you can watch your 4-20ma flow through the meter.

Once you have your 0-10V, pop a 500ohm resistor in parallel with the input to get 0-20ma??? 5V inputs use a 250ohm resistor to convert from 4-20ma. I think I'm wrong though, as you are working outputs, not inputs.

Put all your devices in 2-10V, 
4-20ma is highly prone to interference.

Someone will have to help work this out. But it beats $500 for the stroking you want to do. 

...........................


You need to get the laptop going and hookup to the controller, because you need to manually stroke the output from the controller to verify end-to-end that the controller is good too. 

Talk to the computer side's PM. He will buy you a netbook to stroke the devices if it gets his guys off the hook for helping you out.


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## Sawdust454 (Sep 26, 2008)

http://www.omega.com/ppt/pptsc.asp?ref=CL28MA&ttID=CL28MA&Nav=

I use model cL-304, but I see that it has been discontinued.
The link above is the replacement for the 304. It however is $495.00


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## 76nemo (Aug 13, 2008)

mattsilkwood said:


> I believe the fluke 789 (model#?) is what you are after. It is a 4-20mA source. It's also quite a bit higher than 400 bucks.


 
The http://www.fluke773.com/ has far surpassed the 789, and so hasn't it's price tag:thumbsup:


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## gesparky221 (Nov 30, 2007)

Check out this simple 4-20ma supply from Martel Electronics. Thier web site is www.martelcorp.com. This is a no frills supply we use in our shop for controllers and actuators. I don't remember if we purchased it direct or thru a vendor. The one we use is a MS-420 Loop calibrator.


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## John (Jan 22, 2007)

EXTECH 412355A $286.00

http://www.grainger.com/Grainger/items/1LYR3?Pid=search


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## Advanced37 (Jan 11, 2010)

John said:


> EXTECH 412355A $286.00
> 
> http://www.grainger.com/Grainger/items/1LYR3?Pid=search


I have this one works fine...


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## MDShunk (Jan 7, 2007)

gesparky221 said:


> Check out this simple 4-20ma supply from Martel Electronics. Thier web site is www.martelcorp.com. This is a no frills supply we use in our shop for controllers and actuators. I don't remember if we purchased it direct or thru a vendor. The one we use is a MS-420 Loop calibrator.


An Omron rep gave me that loop calibrator (slightly different model number and case style) a good many years ago. It works fine. I think mine is lcc421, or one very similar.


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## John (Jan 22, 2007)

John said:


> EXTECH 412355A $286.00
> 
> http://www.grainger.com/Grainger/items/1LYR3?Pid=search


Also for a little more $$ it can be NIST. :thumbsup:


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## PRECISION_JC (Apr 6, 2010)

*Extech 412355A Current and Voltage Calibrator/Met*


This is the one I use and It works great for about $250.00


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