Simrad AP70 Installation Manual page 24

+ -
POLARITY
CHECK
SUPPLY
24 |
T
12/24V DC
Network LEN
When you have a larger system with network power in center of the backbone you should
make the installation such that the load/current draw from the devices in each side/branch is
equal.
For LEN numbers, see "Specifications" on page 70.
¼ Note:
1 LEN (Load Equivalency Number) equals 50 mA current draw.
1 2 2 2
LEN LEN LEN LEN
T
(12 LEN)
Powering drive units
AC70 computer requires separate power supply for drive units. Refer "Autopilot computers" on
page 27.
Polarity protection
For supply to SI80 and AC70 boards, pay special attention to polarity protection.
The main supply fuse for these units is supplied loose in the bag with the cable plugs, and it
should not be put in place before polarity is checked.
1.
Connect the power wires, and verify that the green diode is lit
-
A red diode indicates wrong polarity, and the wires must be swapped
2.
Switch off the power supply voltage and put the fuse into correct position
The illustration shows power terminal and diodes on the AC70 board. For location of
terminals, fuse and diodes on the board, refer to the illustration inside the computer unit.
Wiring | AP70/AP80 Installation Manual

12/24V DC
12/24V DC
2 3
LEN LEN LEN
12 V DC
SI80
4 3 2
LEN LEN
(12 LEN)
T
3
LEN
T