5069 SA Power

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The CompactLogix 5380 controllers require 2 power connections to the system – MOD power and SA power.

MOD Power (module or system power) powers the CompactLogix 5380 system and lets modules transfer data and execute logic. System power is provided through the MOD Power connection and will always be 24VDC.
MOD power is passed along from controller to all I/O modules through the entire bus.


What is SA power?

SA (Sensor/Actuator) power provides field power for 5069 Compact I/O modules and field-side devices that are connected to them. Field-side power is provided through the SA Power connection and can be either DC or AC depending on the IO modules that are connected immediately afterwards. SA Power is passed from controller to I/O modules unless a 5069-FPD is used. The 5069-FPD (field potential distributor) will break the SA Power distribution system and allow a new SA power bus to the right. A 5069-FPD can be used to switch SA power from AC to DC (or vice versa), isolate modules (keep digital power separate from analog) and or to ensure a limited number of modules to a specific power system (there is a 10A max that is supported). If no modules are connected to the controller (e.g. the controller is used with Remote I/O) then SA power does not need to be connected.

Connect external power supplies to removable terminal blocks (RTBs) to provide MOD power and SA power.

The catalog number for the SA Power terminal block is 5069-RTB6-SCREW or 5069-RTB6-SPRING and can be order via catalog number 5069-RTB64-SCREW or 5069-RTB64-SPRING (this includes the RTB for MOD power in the kit).

MOD power is a DC power source that is required to operate the CompactLogix 5380 system. Remember the following:

  • Every module in the system draws current from the MOD power bus and passes the remaining current to the next module.
  • MOD power lets 5069 Compact I/O modules transfer data and the CompactLogix 5380 controller execute logic.
  • A CompactLogix 5380 system uses only one MOD power bus.
  • You must limit the MOD power source to 10 A, max, at 18…32V DC.
  • It is recommended to use an external power supply that is adequately sized for the total MOD power bus current draw in the system. For example, if the total MOD power current draw is 5 A, you can use a MOD power supply that is limited to 5 A.  You must consider current inrush requirements when you calculate the total MOD power bus current draw in the system.

SA power provides power to devices that are connected to some of the 5069 Compact I/O modules in the CompactLogix 5380 system.

  • Some 5069 Compact I/O modules draw current from the SA power bus and pass the remaining current to the next module.
  • Some 5069 Compact I/O modules only pass current along the SA power bus to the next module.
  • You must limit the SA power source to one of the following:
    • If you use DC voltage, you must limit the SA power source to 10 A, max at 18…32V DC.
    • If you use AC voltage, you must limit the SA power source to 10 A, max at 18…240V AC.
  • It is recommended to use an external power supply that is adequately sized for the total SA power bus current draw in the system.

It is also recommend that you use separate external power supplies for MOD power and SA power, respectively. This practice can help prevent unintended consequences that can result if you use one supply. If you use separate external power supplies, the loss of power from one external power supply does not affect the availability of power from the other supply. For example, if separate MOD and SA external power supplies are used and SA power is lost, MOD power remains available for the CompactLogix 5380 controller and Compact 5000 I/O modules. As such, data transfer continues in the system.

For more information, see the CompactLogix 5380 Controllers User Manual Publication 5069-UM001A.


What 5069 I/O module require SA power?

The following table identifies the 5069 I/O modules and what type of Sensor/Actuator (SA) Power is required for the module to operate (SA Power Type (AC/DC)) and also if SA power is consumed.​​​​​​​


5069 ModuleSA Power Type (AC/DC)Termination connection options
Digital IO Modules


AC Input



IA16ACN
DC Input



IB16DCN

IB16FDCN

IB16F-3WDCY
AC Output



OA16ACN
DC Output



OB8DCY-Local Only

OB16DCY-Local Only

OB16FDCY-Local Only

OB16KDCY-Local Only

OBV8SDCY-Local Only

OBV8SKDCY-Local Only
Relay Output



OW4IDCN

OW16DCN

OX4IDCN
Analog IO Modules


Analog Input



IY4DCN

IF8DCN
Analog Output



OF4DCN

OF8DCN
Specialty Modules


High Speed Counter (HSC)HSC2XOB4DCN
SerialSerialDCN
Ethernet Adapters



AENTRDCN/A


AC

AEN2TRDCN/A


ACN/A

When do I need to use the 5069-FPD?

The 5069-FPD (field potential distributor) will break the SA Power distribution system and allow a new SA power bus to the right. A 5069-FPD can be used to switch SA power from AC to DC (or vice versa), isolate modules (keep digital power separate from analog) and or to ensure a limited number of modules to a specific power system (there is a 10A max that is supported).

A 5069-FPD field potential distributor can be used for the following:

  • Configure a 5069 Compact I/O system in which groups of modules are isolated as necessary.
  • Provide additional SA power bus current in a 5069 Compact I/O system. This is necessary when the number of I/O modules collectively draw more than 10 A from the SA power.

DC input modules and analog modules can exist in the same SA Power Bus and do not have to be isolated using the 5069-FPD. The recommendation to isolate all discrete I/O modules from analog in the CompactLogix 5380 Controllers User Manual Publication 5069-UM001 is to prevent noise coupling.

NOTE: If the discrete I/O modules in use are AC then a 5069-FPD (Field Potential Distributor) would be required to separate and isolate the SA power buses.


What 5069 I/O modules require Local Actuator (LA) power connections?

Local Actuator (LA) Power is field-side power that some Compact 5000 I/O modules use instead of SA power. Modules that use LA power do not use SA power. They only pass SA power to the next to the next I/O module in the system.

These output module require LA+ and LA- power connections:

  • 5069-OB8
  • 5069-OB16
  • 5069-OB16F

Even though these modules do not use the SA power, the modules that use LA Power must be installed on the SA Power bus of the module type. For example, you must install a 5069-OB8 module on an SA Power bus that includes DC type modules.


5069 References:


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