Mitsubishi Electric FR-A5NPA Instruction Manual page 11

INSTALLATION
(6) To remove the option unit, remove the two left and right screws, and
then hold the option unit and pull its bottom toward you as shown in the
figure. (The option unit is fixed by the hook of the inverter.)
REMARKS
Perform wiring after the option unit (FR-A5NPA) was fitted and the inverter front
cover was mounted.
The option unit (FR-A5NPA) is valid only if it is fitted in slot 3.
When two or more communication option units are mounted, "E.OPT" error is
displayed. Note that when the relay output/computer link unit (FR-A5NR) is
mounted, only relay output is activated.
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