Allen-Bradley GuardLogix 5570 User Manual page 43

Follow these steps to remove a 1756-ESMCAP(XT), 1756-ESMNSE(XT), or
1756-SPESMNSE(XT) module.
WARNING: If your application requires the ESM to deplete its residual stored
energy to 40 μJoule or less before you transport it into or out of the
application, you must use the 1756-ESMNSE(XT) module for the primary
controller and the 1756-SPESMNSE(XT) for the safety partner. In this case,
complete these steps before you remove the ESM.
a. Turn power off to the chassis.
After you turn power off to the chassis, the controller's OK status indicator
transitions from Green to Solid Red to OFF.
b. Wait at least 20 minutes for the residual stored energy to decrease to 40 μJ
or less before you remove the ESM.
There is no visual indication of when the 20 minutes has expired. You must
track that time period.
WARNING: When you insert or remove the energy storage module while
backplane power is on, an electric arc can occur. This could cause an
explosion in hazardous location installations.
Be sure that power is removed or the area is nonhazardous before proceeding.
Repeated electric arcing causes excessive wear to contacts on both the module
and its mating connector.
1. Remove the key from the key switch.
IMPORTANT The next step depends on the conditions that apply to your
Rockwell Automation Publication 1756-UM022D-EN-P - May 2017
application:
• If you are removing the ESM from a powered controller,
go to step 2.
• If you are removing the ESM from a controller that is not
powered, either because the chassis power is turned off or the
controller has been removed from a powered chassis, do not
remove the ESM immediately.
Wait until the controller's OK status indicator transitions from
Green to Solid Red to OFF before you remove the ESM.
After the OK status indicator transitions to OFF, go to
Install the Controller Chapter 2
step 2.
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