CPT AUTOPILOT CPT, Руководство по установке

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CPT Autopilot Installation Manual
© 2018 CPT AUTOPILOT INC. VERSION 21 PAGE 25 OF 26
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If the phone has been exposed to strong magnetic fields the compass will not read accurately due to magnetized
metal inside the phone.
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The phone compass may not be sensitive enough to show changes of less than 3 or 4 degrees.
With your boat parallel to the dock, stand on the dock and check the dock’s heading and the boat’s heading with the
magnetic compass. Step on the boat, hold the compass 3' above or away from the pedestal and take a reading. The two
headings should be very similar. Keeping the compass oriented, approach the pedestal area and watch the needle to notice
any deflection from magnetic fields. Next place a yardstick or a firm wooden straight-edge against the pedestal guardrail
and rest it firmly on the deck. Hold the straight-edge steady, so it doesn’t twist. While holding the compass firmly against
the straight-edge to keep the compass from rotating at all, slowly slide it up and down the straight edge and notice the
amount of needle movement or deflection. The needle must not be pulled or deflected more than 5-degrees near the
mounting area.
You may notice some needle deflection as you pass the area just next to the ship’s compass (there are compensating
magnets in the case) and near the engine control levers. There is usually no needle deflection 6-10
ʺ below this area or 3 ʺ -
4 ʺ above the ship’s compass card. If the needle deflects more than 5°, a more suitable location will need to be found for the
control box.
Some boats may have steel parts that have become magnetized over the years. Magnetism can come from steel in engine
control cables and pins, steering cable fittings, any stainless bolts or dodger fittings that are not 316 SS, homemade
guardrails, and fasteners used for pedestal tables. Welded joints or parts may also be magnetic. On a few boats, the boat’s
engine is located just inches under the pedestal which may cause a problem. Steel boats should do a careful magnetic
survey, and have a mounting location at least 6 ft from the nearest steel.
If a suitable location is not available for the control box, use of the CPT is not recommended.
Apply a thin slice of tape as a marker on the face of
the handheld compass. This will provide a reference
that makes reading the compass needle or card
movement easier.
1. Hold the compass edge firmly against the
straight edge to keep compass oriented without
movement or rotation.
2. Take readings from the deck level to above the
pedestal, next to each guard rail. Repeat the
readings forward and aft of each guardrail.
3. Note any compass needle deflection. Needle
deflection should be less than 5 degrees.
Hiking compasses work well for observing
small needle movements.