How do I calibrate the depth reading on a Raymarine ST60 Multi?

The Raymarine ST60 Multi repeats depth information from another instrument, so you normally set the depth offset at the instrument supplying it. Identify that depth master first, then choose whether the display should show depth below the transducer, below the keel or from the waterline.

Find the depth master

Check the model name on the front panel: an ST60 Multi differs from an ST60 Depth or ST60 Tridata. The Multi displays information received over SeaTalk; its setup menus do not include depth-transducer calibration.

In a typical installation, the transducer cable runs to an ST60 Depth or ST60 Tridata, which supplies the Multi's depth reading. Check the chart table and other cockpit instrument positions, as the master may be away from the helm.

If Grace has been upgraded, the source could be a transducer converter or another sounder connected through an interface. Follow the transducer cable and identify the equipment before changing settings. With an iTC-5 installation, use a compatible calibration controller, such as an i70/i70s, or a supported multifunction display configuration.

Check the source first. Changing the Multi's display preferences will not correct an offset elsewhere in the system.

Choose the depth reference

The offset is a fixed distance added to or subtracted from the depth measured beneath the transducer face. The usual Raymarine depth-offset convention is:

• Transducer reference: use zero offset. The display shows the distance from the transducer face to the seabed.
• Waterline reference: enter a positive offset equal to the distance from the transducer face up to the waterline.
• Keel reference: enter a negative offset equal to the distance from the transducer face down to the lowest part of the boat.

Suppose Grace draws 1.80 m and the transducer face sits 0.40 m below the waterline. The waterline offset is +0.40 m; the keel offset is −1.40 m. A measured transducer depth of 3.00 m would then display 3.40 m from the waterline or 1.60 m beneath the keel.

Do not enter the full 1.80 m draught as a negative offset unless the transducer is at the waterline. This common mistake makes the displayed clearance unnecessarily small.

Set the master's offset

Record the existing offset and depth units before making adjustments. Check whether the master displays metres, feet or fathoms; entering an offset in the wrong units can cause a substantial error.