Help wiring Bennett Auto trim pro and module into existing boat wiring for complete newb

[lazywater]

I'm attempting to install Bennett electric trim tabs (Bolt) with Auto trim pro controls and module. I'm new to boat wiring, so bear with me. I'm trying to figure out the cleanest way to connect to existing wiring (2017 Stingray 198ls). I've decided to mount the module above the battery on the transom next to the engine. The controller will be mounted to the cockpit. I have fished the wiring harness with dt connectors from the helm to the engine compartment where the module will be located.

At the helm, the controller needs to connect the orange wire to 12v power and purple to ignition power (auto retracts tabs when engine is turned off). The helm has a set of switches, many for things that are not installed on the boat. All of the switches run through a set of 5amp relays. The positive hot circuit wiring is standard red and appears to be larger gauge. I thought I would tap the power with a spade splitter on the positive side of the back of one of the relays, connecting orange to red. Pulling the ignition switch, there is a purple wire. I'm assuming I need to connect the purple from the controller to the purple wire coming from the ignition switch. Should I install an inline 5amp fuse on this? Is it best to use a crimp style spade splice to connect to the purple wire? Interestingly, the controller also has a black ground, but the instructions do not say it needs to be connected at the helm? I'm assuming it must be grounded through the dt wiring harness through to the module which makes me wonder why they have an extra black wire.

In the engine bay, the module connects orange to 20a 12v. I was planning to crimp a loop to connect it straight to the battery with an inline 20amp fuse (similar to the bilge). Are there any good water-resistant fuses for this or do I just use a standard auto parts fuse? Black goes to ground. I was planning to crimp a loop to bolt it onto the grounding strip in the vicinity of the battery in the engine compartment. Where do I go to buy the crimp loops and other connectors?
wiring diagram

helm controller location

closeup of helm including factory switches. fresh water, nav/anc, trim tabs not connected to anything from the factory.

underneath helm cover plate for relays

back of relay block associated with cover plate. i wanted to add a spade splitter to the red wire in the lower right corner to connect the orange power at the helm. do i need a 5amp inline fuse? are there better ways/places to connect to power at the helm?

ignition switch wiring. i'm assuming i need to connect the auto trim pro controller purple wire to the purple wire coming from the back of the ignition switch? should i use a tap splice?

better view of ignition switch wiring

random factory unconnected wiring under helm includes purple and black. can i connect to this instead of splicing the ignition wiring?

 

[alldodge]

Hope you have better luck then I've had with Auto TrimPro, I'm on number 6 I think
https://forums.iboats.com/threads/bennett-trim-repair-and-auto-pro-install.696124/

Suggest using the trim pump to supply power to the 20 amp orange connection. It should be easy to get to

Check the block off Purple connection and verify it has 12V when key is turned ON. If it does that would be better then splicing into the key wire

Connect the Orange to Red/Purple at the key so it has power full time.

 

[lazywater]

OK thanks. Let's hope they've improved the design of the ATP to last a bit longer. I'm trying to use the electric Bolt actuators as I didn't want to run hydraulics. Since the boat lives out of the water on a trailer, I'm hoping the seals on the electric actuators will last as long as the boat. I didn't really need the auto leveling, but I am hoping the auto trim will smooth out rough chop or at least allow us to plane at slower speeds. My goal is for my wife to be able to use this system which would require it to be "set and forget."

I guess worst case scenario, we could disable the auto trim feature and use the up/down switches manually. This would defeat the purpose I suppose. There is currently a 6 month wait for the ATP controller because of supply chain chip shortage issues.

 

[lazywater]

Update for anyone tackling this. I initially wired this up to main power and discovered there is no on/off integrated switch. As soon as I connected the battery, the system would light up and remain activated. I called Bennett and they said that the ATP controller is designed to work off of "switchable" helm power. My boat doesn't have that and if you are in the same "boat," you will want to run the orange power off of an on/off toggle switch. Fortunately, my boat had an unused factory installed toggle switch for "trim tabs" that already had power. I ran both orange wires to a piggy back blade splitter on the back of the switch.

I installed a 20amp inline glass fuse for the heavier gauge power supply to the controller module. I connected the purple ignition switched power to a spare purple wire for an unused instrument gauge. I connected all black negative wires to a piggyback blade splitter to the back of the cigarette lighter on the negative pole. This avoided splicing existing boat wiring, but this could have also been accomplished with t-taps or splices. If you have a negative bus nearby, that would be preferable for connecting your black wires to the negative side of the circuit. I added 2.5amp inline glass fuses for the small gauge purple and orange wires. The system functions as expected. I'm not sure these were absolutely necessary, but they were recommended by the Bennett tech. You will need an assortment of blade splitters, butt connectors, and terminal connectors.

 

[alldodge]

No where in the manual nor the many times I talked to Bennett Tech support (MJ Thomas) did they ever say the Orange is on switchable power. The main unit stays ON but draws very little power. Many turn Bat switches OFF when they depart

 

[lazywater]

No where in the manual nor the many times I talked to Bennett Tech support (MJ Thomas) did they ever say the Orange is on switchable power. The main unit stays ON but draws very little power. Many turn Bat switches OFF when they depart

Yep, manual says to connect orange to main helm power. It's also not clear on fuses, though they appear in the diagram. Also spoke to MJ. He said that they assume most boats have "switchable" helm power with on/off switch or battery cutoff switch. My boat has neither so I would have no way to shut this off other than to disconnect the battery. Still doable, but less than ideal. This would not be a problem if the helm control had an integrated power button. I'm sure the LED's don't take a lot of power but I don't want them on all the time. You can also dim or disable the leds. By default there are probably 16-22 lights on the helm control receiving power and a handful on the controller unit. I prefer to switch it on with the factory installed on/off trim tab switch, then turn off the switch after shutting off ignition so the auto retract feature has time to do it's thing. Not much risk of forgetting to turn it off as it lights up like a Christmas tree.

I moved the toggle switch as close as possible to the ATP helm control. Seems relatively intuitive. See images. I could have also wired this off of the ACCY accessory power switch which is also unused on my boat. If you are plugging your battery into a trickle charger during storage and don't mind lights on all the time, it shouldn't be a problem either way.

 

[alldodge]

Also spoke to MJ. He said that they assume most boats have "switchable" helm power with on/off switch or battery cutoff switch.

Mine is a cruiser and yes I have a Bat switch but don't turn it off. Shore power plug in on departure so no issue with Bat