RF45X 2

Upgrade of unit

The Simrad RF45X Rudder Feedback Unit has been through a quality upgrade to improve its EMC performance. This upgrade required a new PCB layout. Additionally a modification was done to the circuitry that made the internal jumper S1 redundant. The S1 jumper is now removed from the PCB. This means that it is no longer necessary to open the unit to switch between an ACXX/J3XX/AP50 and an AP45/AP9Mk3 connection.

The modified units have got revision code FA and the PCB’s have got revision code GA.

Late manual upgrade
The first modified units were sent to customer in early June. Unfortunately, at that stage the mounting instructions were not updated. Approximately one hundred modified units have been sent from our warehouse with the old mounting instructions supplied (20220612, rev. C).
Updated mounting instructions have been supplied with all units that have left the factory since July 1st. The updated instructions (Rev. D) are attached below.
We apologize for the inconvenience this may have caused you, but hope you will be satisfied with the improved RF45X unit.

Simrad RF45X Rudder Feedback Unit
Valid for RF45X with code FA onwards.
The RF45X is a medium duty rudder feedback unit. Mechanically it is identical to it’s predecessor RF45, therefore it is a repairable rather than a potted throw away item. Electrically it outputs a frequency (pulse width modulated) signal that matches with the ACXX/J3XX/J50 input (AP25/AP20/AP35/AP50), and also with AP45 and AP9 Mk3. The RF45X can also operate on 24V DC, a useful feature when connected in a stand alone rudder angle indicator system.

Connection to AP45 Autopilot
Refer to the AP45 manual for mounting and connection details. Connection to ACXX/J3XX/J50 junction units.

Mounting
The RF45X is normally installed with the shaft pointing upwards. It can, however, be mounted with the shaft pointing downwards if this is more convenient. The deflection can then be inverted as illustrated in Figure 2. An “upside-down” installation will make access to within the unit more convenient as the unit can be opened without moving it from the mounting base.

To open the unit, unscrew the two screws at the bottom and remove the cover. Be careful with the wires when you put back the cover. The unit is secured to the mounting base by the two enclosed Allen screws. (Other types of screws may be used when it is secured to e.g. a wooden base.)
Make the parallelogram configuration of the transmission link with the rudder amidships and temporarily fasten the link to the RF45X shaft. The transmission rod can be shortened by cutting off a piece using hacksaw. Move the rudder manually h.o. - h.o. and make sure the transmission link is moving freely in both directions.

Electrical connection
Use a twisted pair cable AWG20 (0.5 mm2) between the breakout box and the ACXX/J3XX/J50 junction unit. The cable length is not critical but should be kept at a minimum. The cable should be connected to the ACXX/J3XX/J50 junction unit. When splicing the cables in the breakout box, crimp the enclosed pins on each wire of the extension cable. Otherwise the wires may be cut off at the terminal point when the screws are tightened. The screen is not terminated in RF45X and must be connected in the ACXX/J3XX/J50 junction unit as per instructions in the autopilot manual.
Note!
The green and yellow wire is not used and must be isolated!

ACXX/J3XX/J50 connection
Alignment and calibration
The purpose of this procedure is to make the feedback
unit operate within its active segment. If the unit
operates outside this segment there will be a feedback failure alarm.

1. Position the rudder amidships.
2. Loosen the two screws that secure the
transmission lever to the RF45X shaft.
P/N 20220612D Page 3 of 3 30.06.05
3. Bring up the Standby mode to show the rudder angle.
4. Use a flat screwdriver in the slot and adjust the rudder angle to zero degrees on the display.
5. Secure the transmission lever to the shaft and proceed with the normal installation setup as per the autopilot manual.
Note!
If the autopilot presents you with a Rudder Feedback Alarm after turn on, proceed as follows:

• Turn the autopilot off. Use a flat screwdriver in the slot and turn the shaft 180°.
• Proceed from paragraph 3 above.

Spare Parts
22011290 RF45X Rudder Feedback Unit
22011217 Mounting kit
22011258 RF45X PCB Ass’y with potentiometer (10K)
22011365 Potentiometer (10K) with wires
22011183 RF45 Transmission Link
44132322 Transmission rod M8x30 (2)
22504054 Joint Nut M8
44157097 Ball Joint Socket
22011209 Ball Joint Pin
22504039 Transmission lever

Regards Frank.