Fujitsu MB2147-01 Application Note page 47

I Connection of DSU-FR Cable to Flat Cable (for DSU-4)
CAUTION
Prohibition
Figure 2.2-2 Connection of DSU-FR Cable to Flat Cable (DSU-4)
Lock levers
To connect the flat cable, open the lock levers of the flat cable connector, insert
the flat cable, and then close the lock levers.
To remove the flat cable, open the lock levers of the flat cable connector, unplug
the connector, and then close the lock levers.
2.2 Connection of DSU-FR Cable to Attached Cable
Make sure that power to the product is turned off and the power plug is
disconnected from outlets before connecting or disconnecting cables.
Doing so may result in device problems or electric shock.
Grasp connectors when connecting or disconnecting a cable. Do not
grasp the cable. Doing so may result in device problems or electric
shock.
Flat cable
Flat cable connector
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