JRC JMR-92 Series Field Service Manual page 689

When UPS has been connected to the Relay terminal block, be sure to set the
"Bat-Select" rotary switch at "Service" on the UPS controller. Furthermore, be sure to
eject the fuse of the UPS battery.
Not following this instruction will cause electric shock and/or malfunction.
Step 4 Dismount the terminal block from DIN rail bracket
At first, dismount the right-side endplate. It can be removed from the DIN rail using the principle
of leverage, by inserting a 3 mm width flat head screwdriver into its groove.
Next, dismount the terminal block. It can be removed by sliding itself along the DIN rail.
Chapter 4 Replacement procedure 4-468