Need help with adding module (DI,Do and 1769-HSC)

[PaulKim1003 3]

Hi,

I have few questions with adding module.

I would like to add Di,Do and 1734-vhsc24 card.

can 1734-EP24DC handle the 3 cards?

is there a limit?? how do i find it out??

is 1734-Ep24dc added because 1734-AENT can not supply enough power for all the cards??

Thanks 

 

Edited 22 Dec 2015 by PaulKim1003

[rdrast 3]

Yes, the EP24DC is used to provide another voltage source to the devices downstream from it (to the right).  You don't want to pass too much current through the buss, so adding a separate distribution module shares the load.  You can add another if you need.  These are similar to the FPD module, which allows providing 120VAC downstream to 120VAC modules.

If I recall correctly, the AENT can support up to 63 modules.  The buss limits are a maximum of 10Amps per group, so for every expected 10A load, you need an EP24DC.  Rockwell specifies (without doing a current calculation) a maximum of 13 modules between power sources, either the adapter, or EP24DC's.

See Here

 

[ScottC 8]

Yes, the 1734-EP24DC can handle the three additional modules. Yes there is a limit. You can find the limits in the Bulletin 1734 Selection Guide. You can also download and install Rockwell Automation's Integrated Architecture Builder, which will allow you to configure your rack. It automatically does the calculations and inserts additional power supplies as needed.

Some of rdrast's comments are not accurate. The POINT I/O series has two buses to be concerned with - POINTBus and Field Power Bus. The POINTBus supplies operating power to the modules. The current requirements for the modules vary from 75mA to 220mA or more. The 1734-AENT adapter can supply up to 1000mA for the POINTbus. The EP24DC and EPAC can expand the POINTBus an additional 1300mA (1000mA if mounted vertically) for modules to the right. The EP24DC is for 24VDC supplies and the EPAC is for 120/240VAC supplies. The EP24DC and EPAC can also be used to break the Field Power Bus if you want to segment or partition your system (inputs, outputs, digital, analog, etc.). Note: If you are using 120/240VAC modules, you must have an EPAC expansion power supply in the system. 120/240VAC cannot be connected to the AENT.

The Field Power Bus supplies power to the field devices. The AENT can provide 9A (1A goes to adapter itself) of current for field devices to its right. The EP24DC and EPAC can provide 10A of current for field devices to their right.

The 1734-FPD is only used to break the Field Power Bus. It does not expand the POINTBus. It can be used for 5-125VDC or 24-240VAC field applications. The FPD can provide 10A of current for field devices to its right.