Nick_H
Well-Known Member
A couple of people asked me to report on the auto tabs once i'd tried them, so here goes.
They were cheap at £245 all in from PH Marine, so no big risk to try them, and easy to install once you know how, although the manual can be confusing. You install it differently depending on whether you have a "Manual Control System", or an "Electronic Indicator Control System". My boat has electronic indicators, which are connected by wiring ribbons to a "Central Processor Unit III", which had a socket marked "from attitude sensor for auto tab control", so I set about following the EIC instructions and got totally confused. PH Marine put me on to super helpful guy at Bennett UK, who explained I had something called "trimdicators" (of which there is no mention in the manual), and that I should follow the instructions for the manual system, and completely ignore the existing processor and indicators. Given that this is all Bennett original equipment of only 2004 vintage, this set up should really have been covered in the manual. If I hadn't phoned Bennett UK, i'd still be there now.
On Monday I got to use them properly for the first time on a cruise up the Solent from Lym to Cowes for lunch. You manually set the boat to the correct trim level at planing speed, then set the system to remember that setting. You can then at any time press the "on" button and the tabs will automatically try to recreate the same trim levels. They do this by averaging out the attitude readings over a period, which seems to be about 10 secs. The idea of this that they don't try to correct a boat rolling from side to side, or to level the boat in short turns. This is necessary, but on my boat at least it causes a problem.
Imagine yourself cruising along, and the boat is leaning a bit to stbd, so you turn the auto tabs on. After a few seconds the sytem automatically lowers the stbd tab to try and correct the lean, but lowering the tab also affects the steering, so the boat starts to veer slightly to the right. In response you turn the wheel to steer to port, which of course causes the boat to lean to port, so after a few seconds the stbd tab raises and the port tab lowers in order to correct it. This causes the boat to veer to port, so you steer to starboard, and the whole cycle starts again.
The result is that you tend to zig zag along slightly, and the need to make regular corrections to the trim is replaced by the need to make regular corrections to the steering. I think the problem is likely to be exaggerated on the Windy, as it leans heavily into even shallow turns. It's not a major problem, more of an annoyance, but then having to adjust the trim tabs manually wasn't a major problem either, so i'm not sure i've gained a lot.
I think it may be more useful on longer cruises, and may possibly work well in conjunction with an autopilot, which I don't have on the Windy. I'll persevere, and may find that I can predict the steering effect of the tabs better, and only correct half of the oversteer with the wheel, recognising the trim tabs will do the other half.
So I give them a dissappointing 4 out of 10, or 9 out of 10 if you're an MBM/MBY reader
They were cheap at £245 all in from PH Marine, so no big risk to try them, and easy to install once you know how, although the manual can be confusing. You install it differently depending on whether you have a "Manual Control System", or an "Electronic Indicator Control System". My boat has electronic indicators, which are connected by wiring ribbons to a "Central Processor Unit III", which had a socket marked "from attitude sensor for auto tab control", so I set about following the EIC instructions and got totally confused. PH Marine put me on to super helpful guy at Bennett UK, who explained I had something called "trimdicators" (of which there is no mention in the manual), and that I should follow the instructions for the manual system, and completely ignore the existing processor and indicators. Given that this is all Bennett original equipment of only 2004 vintage, this set up should really have been covered in the manual. If I hadn't phoned Bennett UK, i'd still be there now.
On Monday I got to use them properly for the first time on a cruise up the Solent from Lym to Cowes for lunch. You manually set the boat to the correct trim level at planing speed, then set the system to remember that setting. You can then at any time press the "on" button and the tabs will automatically try to recreate the same trim levels. They do this by averaging out the attitude readings over a period, which seems to be about 10 secs. The idea of this that they don't try to correct a boat rolling from side to side, or to level the boat in short turns. This is necessary, but on my boat at least it causes a problem.
Imagine yourself cruising along, and the boat is leaning a bit to stbd, so you turn the auto tabs on. After a few seconds the sytem automatically lowers the stbd tab to try and correct the lean, but lowering the tab also affects the steering, so the boat starts to veer slightly to the right. In response you turn the wheel to steer to port, which of course causes the boat to lean to port, so after a few seconds the stbd tab raises and the port tab lowers in order to correct it. This causes the boat to veer to port, so you steer to starboard, and the whole cycle starts again.
The result is that you tend to zig zag along slightly, and the need to make regular corrections to the trim is replaced by the need to make regular corrections to the steering. I think the problem is likely to be exaggerated on the Windy, as it leans heavily into even shallow turns. It's not a major problem, more of an annoyance, but then having to adjust the trim tabs manually wasn't a major problem either, so i'm not sure i've gained a lot.
I think it may be more useful on longer cruises, and may possibly work well in conjunction with an autopilot, which I don't have on the Windy. I'll persevere, and may find that I can predict the steering effect of the tabs better, and only correct half of the oversteer with the wheel, recognising the trim tabs will do the other half.
So I give them a dissappointing 4 out of 10, or 9 out of 10 if you're an MBM/MBY reader
for them.