Elk M1 Relays

[jbauer]

Hey Guys,

This is kind of a follow up to a previous question. I am looking to control a 1 HP motor (13.8 amps), and have decided that I will for sure use the Elk M1 to do it. Elk sells the following relay modules:

http://www.elkproducts.com/products/elk-912.htm

These modules are rated at 10 Amps, so I assume I have to stack it to another contactor that is capable of the full load, such as one of these:

http://www.functionaldevices.com/ChartPilot.html

Is this the proper way to switch a larger motor with HA equipment?

- jason

 

[WayneW]

Yes, that will work or you should be able to drive the RIB directly from one of the Elk outputs. If I recall correctly, the M1 can output 50 mA and the RIBS are less than that. But an extra relay in the circuit never hurt anything (but your wallet).

 

[Spanky]

The ELK 912 relays can handle 12 to 15 amps resistive, 1/4 horsepower.

To get long life out of the relay contacts you need 30 amp contacts or greater in a contactor.

Here is an example contactor relay:
http://www.hascorelays.com/electro_30_amp_car_series.asp

 

[jbauer]

Yes, that will work or you should be able to drive the RIB directly from one of the Elk outputs. If I recall correctly, the M1 can output 50 mA and the RIBS are less than that. But an extra relay in the circuit never hurt anything (but your wallet).

I just want to make sure that I am not missing something. From what I can tell, the only RIB's capable of 1HP require 24 volts on the coil. The Elk M1 only outputs 12 volts, hence the need for a relay module to fire the RIB, and use the RIB to fire the motor.

Is that correct?

- jason

 

[jbauer]

The ELK 912 relays can handle 12 to 15 amps resistive, 1/4 horsepower.

To get long life out of the relay contacts you need 30 amp contacts or greater in a contactor.

Here is an example contactor relay:
http://www.hascorelays.com/electro_30_amp_car_series.asp

Hey Spanky,

Are you suggesting I just use one of those automotive relays fired directly off the M1?

- jason

 

[WayneW]

I just want to make sure that I am not missing something. From what I can tell, the only RIB's capable of 1HP require 24 volts on the coil. The Elk M1 only outputs 12 volts, hence the need for a relay module to fire the RIB, and use the RIB to fire the motor.

Is that correct?

Sorry, you are exactly correct as I forgot about the 24V coil issue. If you used a RIB with a 12VDC coil or a different 12VDC contactor, then you could probably drive it directly (just watch the current).

I don't know if the relay that Spanky linked to would be good for your 1HP load. I err on the side of caution if the relay doesn't give a HP rating. But the amp rating look like it should work.

 

[ano]

I don't know if the relay that Spanky linked to would be good for your 1HP load.

The contact VOLTAGE rating on that relay is 14V DC. Doesn't the 1HP motor run on 120V or 240V AC? If so, its certainly not rated for that load, whether is rated for 30 amps or 10,000 amps. You need a relay whose contacts (not coil) is rated for the HP AND the current AND the voltage of the load, or higher.

 

[mustangcoupe]

Jason I believe your relay solution is the best as yes the elk output will limit you there and the lower voltage relays don't handle the 120 VAC on the contacts (or if you find them I bet they are expensive)

 

[Spanky]

The 30 amp contactor has an 80 ohm coil at 12 volts which is too much current to drive directly from the low current transistor drive outputs on a output expander. You would need to drive the contactor through a relay on the output expander.

 

[murlyns]

Hi

I am just in the process of automating my pool pump just wondering if anyone had a sales outlet that they have used for.

http://www.functionaldevices.com/ChartPilot.html.

Thanks

 

[WayneW]

I am just in the process of automating my pool pump just wondering if anyone had a sales outlet that they have used for.

http://www.functionaldevices.com/ChartPilot.html.

I have used Dynacon a couple of times with good results. They don't do retail sales, so you might need to "act like a business" and they have a $25 minimum order, but their prices are great. I haven't had any luck in getting my favorite Outlet to stock them.

http://www.dynacononline.com/index.htm

 

[DavidL]

You might look into a Sprinkler Pump Relay which is directly controllable via a ELK relay output.
These Pump relays handle 30 amp 220 volt (read the specs) and are encased in a nice clean finger proof watertight box for a nice install (indoors or out).