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Point I/O Modules compatibility

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Hi everybody, my question is simple: Is it possible to use a module 1734-FPD to change the field power distribution source for 1734-OW4? I don't find any answer in all the documents nether no objections/contraindications to get together. Any help appreciated Thanks

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The 1734-OW4 does not connect to the Field Power bus of the POINT I/O assembly, so it doesn't matter what voltage is on the Field Power bus. What voltages are you going to run through the relay contacts of this module ?

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I wanted to use 1 module for 220V AC and another couple FPD/OW4 in 48VAC

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http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1734-in059_-en-p.pdf is stating that the 1734-FPD is used to switch the field power distribution for the I/O modules located to the right of it; obviously, this applies only to the Digital I/O modules. The 1734-OW4 is a RELAY OUTPUT MODULE meaning that both sides of the relays' contacts are independent of the backplane supplied power; you could use any voltages within the min/max ratings of the contacts. According to http://literature.rockwellautomation.com/idc/groups/literature/documents/in/1734-in055_-en-e.pdf the ratings of the 1734-OW4 modules are 5…30V DC @ 2.0 A resistive 120V AC @ 2.0 A resistive 240V AC @ 2.0 A resistive 1800 VA make, 180 VA break I believe this is not within your application's requirements since 480V voltages are usually switched via dedicated relays. If you need to switch 480 VAC circuits you could install an intermediate 480 V rated electro-mechanical relay for the power side of your circuit and use the 1734-OW4 relays to command the coil of the power relay. Edited by dmargineau

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Thanks for posting that additional information. The 1734-OW4 is one of the only POINT modules that doesn't connect at all to the field power bus, so you don't need to use 1734-FPD or 1734-EP24DC or 1734-EPAC modules to separate them from the rest of the modules. The 1734-OW2 module is different: the lower terminals on the terminal block do connect to the field power bus, so you can jumper power to the relay contacts if you wish. This is for convenience; the relay contacts are still separate from everything else. The actual voltage (48 VAC or 480 VAC ?) is very important, as are the relay current ratings. Read and understand the module specifications before using it to switch any load.

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Hi , thanks for answering I didn't thought the 48VAC could be a problem but obviously yes. So I have a doubt because in this following document http://literature.rockwellautomation.com/idc/groups/literature/documents/um/1734-um001_-en-p.pdf Rockwell says that for the module OW4 "Supply voltage can range from +5V dc… 240V ac, depending on relay load" so for 220VAC it's ok but for 48VAC wich document to trust?

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The document is correct; the relay can handle up to 240 volts AC. My concern was that your post might have contained a typo: 480 volts AC is a more common industrial voltage than 48 volts AC is. These are ordinary relay contacts: if they can handle the current you expect at the voltage you are using, then you can use them.

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