Simrad ROBERTSON AP45 - Manual (Page 71)

Robertson AP45 Autopilot
Installation
Simrad Robertson AS
Egersund - Norway
Page 5-21
The junction unit is made for bulkhead mounting and secured by two screws. To
minimise length of power cables (thus avoiding voltage drop), it should be
centrally located between mains panel and power unit.
The unit has separate mains supply for autopilot electronics and power unit
motor. This reduces the interference to the autopilot electronics caused by the
motor switching. The power unit supply cable (mains supply) should be of at least
4 mm
2 (AWG10) size. The electronic supply cable should be 1,5 mm 2 (AWG14).
Cables from control unit, rudder feedback unit, power unit and mains supply
should be connected to the terminal blocks according to Fig. 5-26. Strip about 1 cm
(0.4”) of the cable’s insulation and pull the screen backwards to cover the
insulation. Position the straps as shown in Fig. 5-22 and tighten well to make sure
the screen has good contact. Sufficient free cable should be left inside the Junction
Unit so that the P.C. board can be removed for repair without disconnecting the
cables from the terminal board.
Mains supply of 12V, 24V or 32V DC is connected to the MAINS + and -terminals.
The unit has been provided with a polarity test point. Connect only the mains
supply conductor that are supposed to be the MAINS– (minus). Switch on the
mains supply and let the other conductor get into touch with the TP1 test point.
See Fig. 8-11. If the green diode D20 lights, the correct conductor is connected to
MAINS– and the other conductor can be connected to MAINS+. If the red diode
D21 lights the conductors must be interchanged.
A separate autopilot (electronic) + supply line is connected to terminal no. 17 (+).
At 32V DC mains the external J101A/32V Adapter must be connected between the
mains + and terminal 17 (ref. Fig. 5-26).
Note!
When using a RPU pump unit, the “Soft start” function should be activated by
connecting a strap between terminal 2 and 4. See Fig. 3-8.
Fig. 5-22
J45A Junction Unit grounding
J45A Junction Unit