Hatch Lift Help!

[Craig]

After almost a year, I'm ready to go boating again :beer I have two electric rams on the hatch. Both have always been slow and one lagged. Then one wouldn't work at all. I pulled it out and hooked it direct to a battery. It works and goes faster than ever. I guess it the way it's wired from the dash.Wires too small, no relay. Anyone know what relay to use and how to wire it to the hatch switch I want to boat again!

 

[Guest]

Something along the lines of the Banderlog relay for diverters....put a relay in back, close to the batteries, and just run signal power from the switch.....or better yet....Dana Hydraulic hatch hinge lifts.....open to close in 2 seconds....:thumbsup

 

[Ziggy]

Something along the lines of the Banderlog relay for diverters....put a relay in back, close to the batteries, and just run signal power from the switch.....or better yet....Dana Hydraulic hatch hinge lifts.....open to close in 2 seconds....:thumbsup

I love my Dana's......no hinges to rack the tailbone on either

 

[RiverDave]

After almost a year, I'm ready to go boating again :beer I have two electric rams on the hatch. Both have always been slow and one lagged. Then one wouldn't work at all. I pulled it out and hooked it direct to a battery. It works and goes faster than ever. I guess it the way it's wired from the dash.Wires too small, no relay. Anyone know what relay to use and how to wire it to the hatch switch I want to boat again!

Craig, put a copy of this post in the B&D section. I'm sure Brian would be happy to answer your question!

RD

 

[Rexone]

This may help

 

[Craig]

I'll do that RD. Rexone, I'll check the voltage today, I assume it should be 12 volts to the motor? Mine is two small wires coming all the way back. Given how much quicker it was when I put it right to the battery, the 10 gauge should help.

 

[Tom Brown]

I'll do that RD. Rexone, I'll check the voltage today, I assume it should be 12 volts to the motor?

No doubt, it's getting 12 volts and will test fine. The problem is, system resistance under load will cause the voltage to sag way down.

My bet is that it tests fine when sitting there but you will see the voltage across the poles of the motor drop to almost nothing when you hit the hatch up switch.

A rear relay system to shorten the circuit path and correctly sized feed wire will take care of that.

Mine is two small wires coming all the way back. Given how much quicker it was when I put it right to the battery, the 10 gauge should help.

Larger gauge wire will fix it. The relays are a more elegant and slightly better solution but the wire can be sized such that it will work perfectly over that distance.

 

[Chico&Zeus]

I had the same problem as you in my old boat....I tried to order one of these from Rex....just my luck, the day I need one, he discontinues them

Check the other marine places (Eddie, Dana, CP Performance)....someone still carries the relay boxes, I think Rex was the only one to have a dual unit that ran both actuators off of one relay though.

 

[spectras only]

All you need is two Bosch relays from Napa , $ 7 ea. I only have one actuator and the hatch goes up fast .

Found these even cheaper > http://www.partsexpress.com/pe/showdetl.cfm?&DID=7&Partnumber=330-073

 

[Outnumbered]

I'd go relay for sure. Re-routing that #10 wire will be a pain in the ass and still wont carry the current of the relay. You can even mount a $10 Ford starter relay from Autozone. They are simple, cheap, and common/easy to find. Buy two and keep a spare. If you need help hooking one up let me know.

 

[Tom Brown]

All you need is two Bosch relays from Napa , $ 7 ea. I only have one hatch actuator and the hatch goes up fast .

I was wondering what justifies the cost of charging $80 for a relay and a plastic box with some wire tails hanging out of it.

Personally, I'd look for a solid state relay, or at least a waterproof relay, to mitigate the danger of spark vapor ignition.

 

[spectras only]

Tom , I'm using the existing wires from the dash switch to the two Bosch relays that mounted next to the actuator . These relays are molded plastic and I've coated them with silicon [ no way its a hazard ] to protect the wiring connections as well . Never understood why the boat manufacturers not using relays in most of the time :hmm .You can have them potted in a box to be proved to marine standards , just like the MSD
blue box .

 

[Craig]

I have two wires coming out of the actuator. My understanding is that to make the ram go out, power is supplied to one and one as ground. Then the power and ground are switched between the two to have the ram retract. Now if you have a relay that works like this diagram. How would you switch the power around to get two functions? Would you just use wires 85 and 87 to the ram and let the dash switch still change it.

 

[Outnumbered]

I forgot about the reverse, so you will actually need two relays. Here is a good example on how to do it...

http://www.commandocaralarms.com/info_spdt_relays.asp

Be sure to use relays that can handle the amp load and run both actuators to the relay set so they will be in perfect synch. You could use 4 relays (a pair for each) but this may get out of synch. Use heavy gage wire in the high-amp circuit to minimize voltage loss--at least 10 or even 8 gage.

 

[spectras only]

You need two relays to reverse polarity [ up/down operation ] to the actuator motor .

http://www.the12volt.com/installbay/uploads/push_switch_motor_control.gif

 

[Retired Member]

Here's another. I drew this up for someone for a trim pump, but it's basically the same idea.

 

[Craig]

oK, it's clearer now, I an see how to wire it, but I just have two questions still, any idea what size fuses to use and where do you buy these relays? Any particluar brands, construction etc?

Thanks to all for the help :thumbsup

Craig

 

[Rexone]

I had the same problem as you in my old boat....I tried to order one of these from Rex....just my luck, the day I need one, he discontinues them

We discontinued the relay boxes due to inconsistant and inadequate quality control of the relays. We used Bosch, and several other brands trying to find something that was consistant, including the brand MSD sells (they are not made by MSD). Finally after numerous comebacks and unhappy customers we just threw in the towel on the relay boxes. When they work they work well. When the fail they don't work at all.

That is why I now just prefer the 10 ga wire and the problem goes away with no components that are prone to failing under the amp load of these motors. Less amps on these relays works well. But these motors with heavy hatches pull some amps and regardless of the amp rating of the relay (we went way overkill) they were still failing. By the time we'd see the failures in the field we'd have dozens of boxes out there with that batch of relays inside. It was not a happy scenario.

Hope that explains some as to the why.

 

[Outnumbered]

I would just stick to a Bosch relay set found at just about any auto parts or car audio store. Mount them under the rear bench seat so if they fail they are accessible. They can be swapped out in 2 minutes. Just keep an extra set in the boat. Use a P-touch and label your wires so they are easy to re-connect. I would get a 30 or 40 amp auto-reset breaker also available at any autoparts store. The breakers are about $4 and would go on the hot side between the relays and the battery.

 

[H2_Whoa]

Just a suggestion, a diode should be added across the coil of the relay. As per : Basic Car Audio Electronics (Relays)

"Anytime that a relay coil is driven by a circuit that is not specifically designed to drive a relay, you should use a quenching/suppression diode connected in parallel with the relay coil. The diagram below will show the connection of the diode. Initially, you may think the diode serves no purpose because the voltage applied to the relay cannot pass through the diode. This is true when the relay is energized. The diode comes into play when the power source is removed from the relay coil. When power is applied to the relay coil, a magnetic field is created and energy is stored in the coil. When power is removed, the magnetic field collapses causing a reverse voltage to be generated (it's called inductive kickback or back EMF). The back EMF can easily reach 200 volts. The diode will absorb the reverse voltage spike. This voltage, if not absorbed by the diode, will cause premature failure of switch contacts and may cause the failure of power switching transistors. You can use virtually any type of rectifier or switching diode (i.e. 1N4001, 1N4002, 1N400x... or Radio Shack part #s 276-1101, 276-1102, 276-1103, 276-1104)."

 

[DrHW]

Ok, there was a thread that had a picture of a relay to use and was pre-wired. I cannot find that thread.

Anyone remember the relay and where to buy it? I rebuilt the actuator once and did not figure out the voltage issue until the actuator motor went out again.

 

[DrHW]

Bump