how to run a Masterflex L/S 7523-90 pump with a USB 6009

[daverrrr]

Hello and thank you for viewing my post. I'm setting up an automated filtration system in my lab. The first instrument I need to interface with is a Masterflex pump.

The only connection to this pump is a DB-25. I've attached a picture of the pinout given in the manual.

The only functionality I need is on/off and speed control. It seemed like a straight forward task at first but I cant figure out what kind of signal to send to the remote start/stop input with the USB 6009. Can anyone offer some advise?

[AnalogKid2DigitalMan]

Since they don't spec a voltage I have a hunch it is looking for a contact closure that connects pin 15 to 17. You may want to 'contact' the manufacturer to verify.

If so, you would need one of the 6008's digital outputs to control a relay. Since it does not have enough current drive to do so directly, you would need a transistor or drive chip between the 6008 output and the relay coil.

-AK2DM

[wm203]

Hi,

I want to run the Masterflex 7521-55 pump with NI USB 6008, is it possible? Could anyone let me know how to do this?

Thanks

Wendy

[Knoxberry]

Hi Wendy,

This thread is fairly old, the orignal authors may not be following it anymore. I would recommend making a new post with your question. I wasn't able to find the Masterflex 7521-55 on their website, so I have no idea how you would use a USB DAQ device to control it. Could you include more information, possibly the data sheet, connection method, etc., in your new post?

Regards, 

[wm203]

Dear Ian,

Many thanks for your reply.

I have tested the pump with a variable voltage power supply, the speed can be controlled by providing 4 - 20 mA, and a 5V for stop/start.  

We have USB6008, if we can get a variable voltage output (2 to 5 V), the speed can be changed from low to high.

Please see attached pics for the pump's info..

I am looking forward to hearing from you.

Kind regards

Wendy

[Knoxberry]

Wendy,

If I read your previous post correctly, the pins that control the speed of the pump require a minimum of 4 mA. If that's true, you could use one of your analog outputs on the 6008 to control the speed of you pump by varying it between 2 and 5V.  You need to be careful though, the 6008 has a maximum current drive of 5 mA. If the pins require a higher current to control the speed of the pump, you won't be able to use the 6008. 

Also, feel free to take a look at the user manual to see if the 6008 meets the specifications required for your application.

Regards,

[wm203]

Dear Ian,

Thanks for your reply, the pump needs 4 - 20 mA for changing the speed from low to high. I will check the 6008's specification for the current limit and whether it has the counter function for timing control as well.

Kind regards

Wendy