Raymarine ST7000, Руководство по установке

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2.1.6 Masthead Transducer (Sail only)
Installation (Fig. 13)
•
With the threaded end of the mounting block I
facing forward, mark the position for the 2 self
tapping screws.
•
Drill the holes using the 4.0mm (5/32in) drill bit
supplied.
•
Attach the mounting block using sealing
compound.
•
Tighten the locking ring 3 very securely.
Cabling
•
Cut the cable with sufficient length to route
from the mounting block to the below deck
junction box.
•
Feed the cable (30m (100 ft) supplied) down
the mast. If the mast is deck stepped the
cable should be passed through the deck and
sealed using a proprietary gland fitting.
•
Connect the cable to the junction box supplied
close to its entry to the vessel to allow mast
unstepping.
•
Route the remainder of the cable back to the
course computer connector box and connect
to AUX 1 terminal.
Note: Do not connect the yellow core. This
should be cut back and insulated.
2.2 Drive Systems
2.2.1 Rotary Drive Unit
The rotary drive unit is coupled to the steering
mechanism by a chain drive. Most steering gear
manufacturers supply special autopilot drive
attachments and many include this facility as
standard.
Having selected the position for attachment of the
autopilot drive chain it is necessary to determine
the chain reduction ratio. Count the number of
turns of the steering gears' shaft (this is the driven
sprocket) when the rudder is driven from hardover
to hardover. Use Fig. 14 to determine the
sprocket sizes required.
These reduction ratios will provide good steering
performance for most vessels with approximately
10 second and 14 second Hardover-Hardover
times for the Type I and Type 2 drive units
respectively. If the vessel is thought to have
unusual steering characteristics, Raymarine's
Product Support Department or one of our
authorised representatives should be contacted
for advice.
Standard 3/8" or 1/2" pitch chain is recommended
for the chain drive and the drive sprocket ideally
should not have less than 15 teeth. Bore and
keyway dimensions for the drive unit sprocket are
detailed in Fig. 15. It is essential that these bore
and keyway dimensions are strictly adhered to.
All sprockets must be keyed and grub screwed to
their shaft and finally secured with 'Loctite'.
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