Open collector output to operate relay

Hi ALL,

I m having digital output with 150mA Max.Current and a Relay of "HLS-CMA3-B" rating:40A/14VDC 560W DC12V.

I need to operate this relay using this DIO(transistor's Open Collector Output).

Is this possible or any pull-up resistor is required if yes need detailed circuit.

Here with the link having details about relay

**broken link removed**


Please reply ASAP.
Thanks

Your relay coil current will be about 160 mA so you want a transistor that can handle 200 mA. You don't state what transistor you are using? Generally with an NPN open collector the emitter goes to gnd and the collector has the load between it and VCC (12 Volts) and no pull up. Again, what is the transistor?

Also, though many automotive relays have an internal diode many don't so you want to place a diode like a 1N4002 across the relay coil with the cathode on the positive side. That will surpress the inductive kick when the relay coil field collapses.

Ron

As Reloadron already mentioned the type of transistor is important for the relay current flow (according to data sheet between 133 and 158mA)

A 2N2222 can easily handle that load.

Activating the relay is done by applying a positive voltage to +CTRL. This voltage must not be less than 0.7V.

Boncuk

Thank you very much as this is valuable input for me.

Regarding the transistor,as i m having information that only DIO (Digital Output)wire from a packed device.

Once again thanks..........

capa_master said:

Regarding the transistor,as i m having information that only DIO (Digital Output)wire from a packed device.

Once again thanks..........

Click to expand...

The digital output from you controlling device should activate the relay.

Boncuk

yes that's right,
This output is having 150mA Max current ratings and the relay rating:40A/14VDC 560W which are switching ratings. Will find more details at Ningbo Helishun Electron Co.,Ltd.

So please suggest if any more changes in above circuit if req.............


Thanks,,,,,,

You want to do it just like Boncuk drew it up. If you look at the data sheet for the relay you linked to they provide the approximate coil resistance for a 12 volt coil. That coil will draw between 133 and 158 mA the latter exceeding your maximum current from your controlling device. That is why the 2N2222 transistor is used to drive the relay. Your relay coil resistance will be between 75.8 and 90 Ohms and thus we can calculate the DC current based on 12 volts. I would do it just as Boncuk has drawn it up.

Ron

Yes..thanks i m going for Boncuk's circuit only......

THANK YOU ALL