ABB ACQ810, Hardware Manual

Page: 85 / 134

Electrical installation 85
Safe torque off (XSTO)
For the drive to start, both connections (OUT1 to IN1, and OUT2 to IN2) must be closed.
By default, the terminal block has jumpers to close the circuit. Remove the jumpers before
connecting an external Safe torque off circuitry to the drive. See page
64 .
„
Control cable connection procedure
See the cable routing on page 86 and connect the control cables as follows:
1. Ground the shields of all control cables connected to the control unit at the clamp
plate. The shields should be continuous as close to the terminals of the control unit as
possible. Only remove the outer jacket of the cable at the cable clamp so that the
clamp presses on the bare shield.
2. Connect the conductors to the appropriate detachable terminals (see page 81) of the
control unit. At the terminal block, use shrink tubing or insulating tape to contain any
stray strands. The shield (especially in case of multiple shields) can also be
terminated with a lug and fastened with a screw at the clamp plate. Leave the other
end of the shield unconnected or ground it indirectly via a few nanofarads high-
frequency capacitor eg, 3.3 nF / 630 V. The shield can also be grounded directly at
both ends if they are
in the same ground line with no significant voltage drop between
the end points.Tighten the screws to secure the connection.
Note: Keep any signal wire pairs twisted as close to the terminals as possible.
Twisting the wire with its return wire reduces disturbances caused by inductive
coupling.