Using NI 6211 to drive a relay

[rockarmatte]

Hi, I have a problem and I hope someone could help me. I'm currently using a NI USB-6211 with Labview 8.6 and want to control a relay. The relay (see attached PDF) will close the secondary side (30 V, 3A) when the primary side gets a current of 5 mA at the voltage of 3 V. Since the analog output only can deliver 2 mA I'm trying to use the digital outputs but I'm not sure I'm doing it right.

So, my questions are:

1) Is it possible to drive the relay with the USB-6211 or do I need to connect some extern power?

2) If possible, how should I connect to + and - wire from the primary side of the relay?

Best regards

Mattias

[Henrik_Volkers · Accepted solution]

To control the relay you can use one of the four digital OUTPUTs of the 6211. They are claimed to sink and source 16mA.

Your relay needs 80mA  (more than the spec allow you to suck out of the 6211) so you have two opportunities:

Use a SSR (solid state relay) they can be powered by the card directly

Or use an external power supply

Be carefull with that relay you have!!! I'm missing the free running diode over the solenoid. *FATZ PENG*

[rockarmatte]

Thanks for your answer Henrik!

As I understand the relay itself require 80 mA in a working condition ( "The current consumption of this relay card is a maximum of about 80 mA" )!

I'm use a 12 volt transformer to supply the relay with power. So far, it shouldn't be any problem, right?

On the other hand, I need a "input 3 ... 12 V => 5 mA" to close the relay contact.

It should be possible to get enough power from a digital port that can provide 16 mA or am I thinking completely wrong?

Solid State Relay sounds like a good alternative ! 'll Investigate further!

[JÞB]

---

On the other hand, I need a "input 3 ... 12 V => 5 mA" to close the relay contact.

It should be possible to get enough power from a digital port that can provide 16 mA or am I thinking completely wrong?

---

Just a bit wrong.  The DIO drives 5 DVC and 16mA max.  you will need a switch! like a transistor 🙂 that your DIO can control to switch the relay coil current.

[rockarmatte]

Thanks Jeff.. Just so I have got everything right..  The relay I'm using includes a transistor since the relay actually uses 12 VDC to operate. So, the input of 5 mA and, lets say, 3 V should be enough to control the transistor which affect the relay. Right?

I'm not really sure why I should use another transistor? Please tell me  = )

Thanks again!

Best regards //Mattias

[JÞB]

Sounds about right.  I didn't look too close at your Relay + driver spec.

[rockarmatte]

Thanks Henrik!

The solid state rely solved my problems!

[Ambyboy]

Hello there.

Please what type or model  of solid state relay are you using and how do you make the connection am having same problem. 

Thanks in advance

[rockarmatte]

Hello,

I can't remember but I think you can use any relay suitable for Arduino, like this one:

https://www.aliexpress.com/item/1pcs-KY-019-5V-One-1-Channel-Relay-Module-Board-Shield-For-PIC-AVR-D...