Lenze TCF Series - Manual (Page 20)

10 CONTROL WIRING
10 .1 CONTROL WIRING VS . POWER WIRING
External control wiring MUST be run in a separate conduit away from all other input and
output power wiring . If control wiring is not kept separate from power wiring, electrical noise
may be generated on the control wiring that will cause erratic drive behavior . Use twisted
wires or shielded cable grounded at the drive chassis ONLY . Recommended control wire is
Belden 8760 or 8770, or equivalent .
NOTE
Control terminals provide basic isolation (insulation per EN 61800-5-1) .
Protection against contact can only be assured by additional measures e .g .
supplemental insulation .
Strip off 0 .20 to 0 .25 inches (5 to 6 mm) of insulation for control wiring, and torque the
terminals to 2 lb-in (0 .2 Nm) . Be careful not to overtorque the terminals, as this will cause
damage to the terminal strip . This is not covered under warranty and can only be repaired by
replacing the control board .
10 .2 TB-2 AND TB-4
The TB-2 terminals are the circuit common for the analog input and analog output functions .
The TB-4 terminals are the reference for all of the digital inputs (TB-1, 13A, 13B, 13C, and
13D) . The digital inputs are active-high as standard, but can be configured for active-low
during initial set-up . Refer to APPENDIX B - INPUT ASSERTION LEVEL . When set for
active-high, TB-4 is at +12 VDC .
NOTE
TB-2 may be connected to chassis ground if noise is a concern . TB-2 must
be connected to chassis ground when using serial communications .
10 .3 SURGE SUPPRESSION ON RELAYS
Current and voltage surges and spikes in the coils of contactors, relays, solenoids, etc, near
or connected to the drive, can cause erratic drive operation . Therefore, a snubber circuit
should be used on coils associated with the drive . For AC coils, snubbers should consist
of a resistor and a capacitor in series across the coil . For DC coils, a free-wheeling or
flyback diode should be placed across the coil . Snubbers are typically available from the
manufacturer of the device .
10 .4 START/STOP CONTROL
There are various control schemes that allow for 2-wire and 3-wire Start/Stop circuits . Refer
to the wiring diagrams in Section 11 - TCF CONTROL WIRING DIAGRAMS
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