[CA] [CA11] Troubleshooting i40 Depth Instrument

[JohnA]

My depthfinder has a mind of its own. It works fine, then will just show 3 dashes. After a while it will resume doing its job of showing the depth. It does not matter deep water or shallow, sailing or motoring slow or fast, calm or rough sea state. My boat is a 1975 vintage Ericson sailboat and I installed the transducer on the starboard side just ahead of the keel. The boat lives in the water year round and so I needed a shoot through transducer. The only transducer the local dealer had was a Raymarine E6608 - a P79 with a plug on the end of the cable. I got a wiring schematic on the internet, cut the plug off and crimped small spade terminals, #3 bare - shield, Blue plus depth#2, Black neg depth #1. The transducer was installed following the instructions closely. I have double checked the connections to the back of the i40 that they are secure and not loose, checked the propylene glycol in the housing etc. The i40 gets power from a fuse panel and the fuse panel is fed directly from the battery and powers the depthfinder, VHF radio and chartplotter. I have tried only using the depthfinder to see if there is a power issue but the problem remains. Is there any way to determine where the problem lies - transducer or i40?
Thanks, John.

[Chuck - Raymarine - Moderator]

Welcome to the Raymarine Forum John,

The reported issue is occurring because the i40 Depth & Bidata instruments are not designed for use within in-hull depth transducers. As much as twenty percent of of the energy from a transducer's ping lost when a transducer pings through a hull. Unlike the i50 Depth and Tridata instruments and the iTC-5, the power output of the i40 Depth and Bidata instruments is exclusively suited to transducers which are in direct contact with the water outside of the hull. Accordingly, while an P79 transducer would have been recommended for use with an i50 Depth, i50 Tridata, or iTC-5, it would not have been recommended for use with an i40 Depth & Bidata instrument. Unless seeking install thru-hull transducer, it would be recommended that the i40 Depth be replaced with i50 Depth or i50 Tridata instrument.

[JohnA]

Hi Chuck
Thanks for clarifying the issue. When I was looking to purchase a new depth finder I asked about the compatibility of using a shoot through transducer and the salesman took the instruction booklet out of the box for the i40 and there is a page where the transducers are listed and the shoot through is listed there. Perhaps this should be updated??
I am not sure about replacing the i40 with an i50, I think I will have to buy a new transducer and haul the boat out of the water to install it.
John

[Chuck - Raymarine - Moderator]

You're welcome and I will notify the documentation team accordingly.