3.5 Compatible drive units
The drive unit interfaces with the vessel’s steering system. The type of drive required depends on the type
of vessel and capacity of the associated steering system.
Raymarine autopilot systems accommodate hydraulic, mechanical and power assisted stern drive systems.
Drive category
Available types
Suitable
ACU
* Max
output
Type 0.5
ACU-100
7 A
Type 1 12 V dc only
ACU-150
12 A
Type 1 12 V / 24 V dc
ACU-200
15 A
Type 2
ACU-400
30 A
Type 3
ACU-400
30 A
Hydraulic pumps
Raymarine autopilots connect to hydraulic steering systems using a rugged
hydraulic pump matched to the capacity of the hydraulic steering system.
To find a suitable pump, you'll need to know the size (in cc) of the hydraulic
cylinder ram(s) mounted to the rudder on vessels featuring an inboard engine,
or to the drive unit on vessels featuring outboard engines. Refer to your steering
system documentation for this information. Alternatively, you can look on the
cylinder ram itself for the brand and model number.
Once you have this figure, refer to the Cylinder Ram Size Chart on the Raymarine
website to determine which hydraulic autopilot pump is compatible with your
vessel's hydraulic steering system:
http://www.raymarine.co.uk/view/?id=209
.
Constant Running
pump (solenoid)
ACU-300
5 A
Type 2
(for vessels
with a maximum
displacement of
22,000 Kg)
ACU-400
30 A
Mechanical hydraulic linear drives
Designed for larger mechanically-steered vessels over 20,000 kg, hydraulic
linear drives consist of a reversing pump, reservoir and hydraulic ram.
A hydraulic linear drive unit connects to the rudder stock via an independent
tiller arm. Accessory fittings from your steering system manufacturer may be
required. The vessel’s steering system must be capable of being back-driven
from the rudder.
Correct drive selection depends on the maximum displacement of your vessel.
Additionally, both the vessel’s fitting structure and the tiller arm (or rudder
quadrant) must be able to cope with the peak levels of thrust generated by the
hydraulic linear drive. For peak thrust data, refer to the technical specification
section of the Hydraulic Linear Drive installation instructions.
Type 3
(for vessels
with a maximum
displacement of
35,000 Kg)
ACU-400
30 A
Type 1
(for vessels
with a maximum
displacement of
11,000 Kg)
ACU-200
15 A
Type 2 Short
(for vessels with
a maximum
displacement of
15,000 Kg)
ACU-400
30 A
Mechanical linear drives
Used in sailing vessels, the mechanical linear drive moves the rudder directly
by pushing the tiller arm or a rudder quadrant.
Correct drive selection depends on the maximum displacement of your vessel.
Type 2 Long
(for vessels with
a maximum
displacement of
20,000 Kg)
ACU-400
30 A
Type 1
(for vessels
with a maximum
displacement of
11,000 Kg)
ACU-200
15 A
Mechanical rotary drives
Designed for power and sailing vessel systems that can be driven from the helm
position through a chain and sprocket e.g. cable and rod.
Optional drive sprockets and modification to the steering chain may be required.
Correct drive selection depends on the maximum displacement of your vessel.
Type 2
(for vessels
with a maximum
displacement of
20,000 Kg)
ACU-400
30 A
17