Installing the Simrad AP28 Autopilot

The Simrad AP28 autopilot system we purchased includes the following units that need to be installed;
AP28 autopilot control head - used to control the autopilot and includes a screen, a knob and buttons.
AC42 control box - this is the brains of the autopilot which also electronics that power the drive unit as well as the means to interface the other components of the autopilot system.
RC42 rate compass - the electronic compass that provides heading data to the AC42
RC300 rudder feedback unit - provides rudder angle data to the AC42
No hydraulic linear drive was purchased as the one from our Northstar autopilot is compatible with the new Simrad system. Most autopilot drives, whether mechanical, hydraulic linear or hydraulic will work with just about any autopilot system, just be sure to ask if your current drive unit is compatible with the new one you're considering.
Before beginning the installation of the autopilot and the NSE multifunction display I had to remove the previously installed Northstar autopilot system and M84 display as described in the previous post.
The installation of the new Simrad AP28 was amazingly simple. First the AC42 control box was mounted in a dry and out of the way area in the lazarette with the four stainless steel screws that were provided. The power supply cable that was already there from the old autopilot system was connected to the AC42 and consisted of 8awg wire. 50 amp fuses were used on both the positive and negative wires. The AC42 has an onboard 30 amp fuse and it has polarity protection, so if you accidently get the power wires installed incorrectly a red light will light on the AC42's circuit board. A green light indicates you installed the power wires with correct polarity.

After connecting the power supply wires I connected the 2 wires from the hydraulic pump to the AC42 and the 2 wires from the pump's solenoid to the AC42. Both sets of wires were already available as they were the same used from the old autopilot. The RF300 rudder feedback unit comes with 33' of cable attached to it and I only needed a run of 10' so the excess was cut off before connecting it to the AC42. I was surprised that the twisted copper wires for the RF300 were not tinned (tinned wires are usually a marine standard). An option to the RF300 is the RF25 which is the same rudder feedback unit but with a SimNet cable attached. The RF300 mounted easily where the old one was mounted as they had the same size base and screw patterns, I was even able to use the same connecting rod from the rudder feedback unit to the steering quadrant.
Next a SimNet cable was connected to the AC42 and then plugged into the SimNet 7-way joiner which provided integration of the autopilot system to the SimNet backbone. The AC42 side of the SimNet cable did not have a plug on it but four wires which were connected to a terminal block on the AC42's circuit board. This completed all the connections required for the AC42 autopilot control box. There are connection points on the AC42 for an optional handheld remote and remote alarm siren, neither of which we chose to install.

The RC42 rate compass was installed near the base of the mast's compression post and its SimNet cable connected to the SimNet backbone via a 7-way joiner. The only remaining unit left now was the AP28 autopilot control head.
Having already cut the hole in the Navpod instrument housing for the AP28 autopilot control head it only took a few minutes to flush mount the AP28 to the Navpod with four screws and attach the corner covers (an optional bracket is available for surface mounting). A six foot SimNet cable was run through the pedestal guard tube, one end connected to the AP28 control head while the other was connected to the SimNet backbone via a 7-way joiner.

And that was it for the installation. I know I've said it many times but Simrad is surprising me with the ease of installing its units that utilize the SimNet system. It takes some time to plan and install the SimNet backbone but once that's done everything else is really easy. Of all the autopilot systems I've installed the Simrad was one of the easiest, especially with integrating to other systems. For those that are looking only for an autopilot system and still wish to integrate with their NMEA0183 systems the Simrad would be a good choice. The Simrad autopilot will integrate easily with any other unit using NMEA0183 data with the use of an optional AT10 SimNet/NMEA0183 converter. And because Simrad's SimNet system is based on the NMEA2000 protocol building onto the SimNet system with future upgrades should be fairly simple.

Okay, so now the Simrad AP28 autopilot system is installed. Before we can start using the autopilot we need to do some dockside and sea trial calibrations. We'll take care of that after we install the NSE-8 multifunction display.