Do I need additional hardware to control solenoids?

[tbob]

Sorry, I misunderstood.  You are correct that the solid state relay could be damaged.  Older DIOs don't have enough current capability to handle relay coils.  I usually use a hex inverter with a UN2003 chip to drive the relay, cheaper than a solid state relay but you must make a PCB or breadboard to wire it up.  New high power DIOs can handle the current without need of a driver.

[jozaeta]

Ok, I think I am getting a clearer picture of the parts I require. Just to be sure, I will require seven 5V relays, seven diodes (with a peak inverse voltate of at least 12V), and a single power supply that can output 12VDC.

I would wire each channel of my DIO to a diode, then from the diode to a relay coil. The other side of the coil would go to ground. The common would wire to the power supply (which I set to output 12VDC?). The normally open contact wires to the solenoid. The other side of the solenoid goes to ground. I leave normally closed wired to nothing.

Is this setup correct?

[K C]

Hi,

A lot of good suggestion and (basic) electronics here. Before you buy everything you think you need; I saw the solenoid on a website but no datasheet. Do you know how much current the solenoid needs. If it's below 1A then you can use the solutions mentioned but if it is several amps you should be careful in choosing the right components.

Do you have more information about the solenoids ?

[tbob]

Jonzaeta:  Your description is not quite accurate.  I guess a picture is worth a thousand words.  Here is a schematic of how it needs to be wired.  Be sure to connect the diode with the polarity as shown.  If your DIO can supply enough current to drive the relay, you can omit the TTL Buffer.  You need to check the specs to be sure.  Also be sure the power supply can handle the current required by the solenoid.  Sometimes a simple wall pack (little square plastic box that plugs right into the wall socket) can be used for a power supply if the current drain is low enough.

Message Edited by tbob on 10-18-2005 10:31 AM

[jozaeta]

Thanks tbob. The picture helped out a lot. I'll be sure to look for a power supply that can provide the proper voltage and current (once I obtain the specs) to the solenoids, and 5V relays. And I'll be sure to wire the diode in the correct direction.

Thanks everyone for the help. It's quite a learning experience for me to work on this project.

[newwb]

Hi,

I could suggest a TI quadruple half-h driver, model number SN754410. I use this driver currently to control 2 24V cole parmer solenoid valves. It has a voltage range of 4.5V to 36V so could easily power your valves. This drivers inputs are compatable with TTL-logic. The question remains as to you needing multiple solenoids to be powered. Maybe several can be interconnected or even kept seperate but with a common power input?

Good luck!
Daniel

[tbob]

Newwb:  Your only about a year late in this reponse.  I think the originator has long since solved his problem.

[K C]

Better late then never, I think