Electric steering for 710/712s

[Hotzenplotz]

The horn was a real pain. I had to machine down the horn contact stud and drill the end of the column opening it up so the contact stud wouldn't touch the inner column.

Newfisher

I also thought about widening the hole in the column, but I did not know how to get the wire out of drill's way ...
So my current plan is to get a set of model railway connectors and cover them with shrinking tube.

Scott

is there any Mog horn button that you know fits intoa version 1 steering wheel ?

[NEWFISHER]

I cut the horn wire to fit and then shoved it down in the column to clear the bit. mark the bit depth with masking tape.

[NEWFISHER]

Today we measured the voltage at the motor and sitting still 12.2. As soon as it sees a load it drops to 9.3. I either have a weak converter or a wiring issue on my end. Installing a stand alone 12v car battery at the foot pedals and temporarily powering the system, it works much better. Not like the video, but I have much wider tires. Ran a stand alone power wire through a 40amp circuit breaker directly to the rear battery ( 12v) and system has good voltage and work much better when parked or " on the rocks" as I am hoping for.

When I ordered the kit, Scott recommended their converter, but I mentioned I had a 90amp unit. Although we both thought it would run the system and all the other items, its apparent that with the large amp draw, it plays nicely with having its own unit. Probably a better idea in the long run. Another reason to always install what's recommended by the guys that have done the installs! I ordered the recommended converter today.

Thanks Scott for the great service and a well thought out system

[rmel]

Hmmm, well if you have a 90A converter installed that should be overkill for
this application -- unless your running a lot of other gear off that simultaneously

What gauge wire and how long of a run is it from the converter to the load?
Also measure the output at the converter at the same time, if that's holding up
you have a wiring problem. Otherwise I'd say your 90A converter has a problem,
check the minimum Input voltage requirement for that convert was well.

Well at least you now know it ain't the Steering unit

ron

[TechMOGogy]

Converter brand could play an issue as well
Some units are rated high but don't actually deliver

[Jimm391730]

It would not surprise me if the PS unit drew 90 amps; at 12 volts that is barely one horsepower of mechanical aid to the steering (90A * 12V = 1084 watts; on HP =746 watts; so almost 1.5HP of electrical power. But motors are not 100% efficient, so 1.5HP electrical is approximately 1HP mechanical). Parked or "on the rocks" you are going to need every bit of power available from the PS unit.

Some power supplies have what is called "remote sense" capability; two separate small wires connect to the + and - right at the PS unit, different wires than the large gauge that carries the 90A. If there is any small voltage drop in the large wires, the small ones feed the reduced voltage back to the supply where it tries to make the voltage at the ends of the large wires the "proper voltage" (12V), and not just 12V at the output of the supply. For example, if you used #12 wires to go 5 feet from the converter to the PS unit (ten feet round trip) then just the wires themselves have 0.016 ohms. At 90 amps, 1.43 volts is lost (subtracted from the 12V) just in the wires themselves; it is not unexpected to lose about that again in connectors, screw terminals, crimps, etc. So it is easy to have 12.000 volts at the output of the converter but only 9V at the PS unit (with a 90A draw). #12 is just too small for that current (even for short durations or distances), you really need #8 or #6 gauge wire for that kind of current. Does this wire come with the kit, and if so, what gauge?

[Garrycol]

Put a 12v battery between a 90 amp 24v/12v battery charger and the power steering and you wont have an issue as the battery will provide surge power requirements. And the battery can be used for powering a whole lot of other accessories.

Garry

[Hotzenplotz]

i can confirm that concept. My power steering is fed from a 17 Ah motorcycle battery .
The battery is topped up by a 25 amps 24 to 12 Volts dc to dc charger.
The whole kit is installed behind the passenger seat.
btw i have a 80 amp fuse on the battery cconnection, and there is a 40 amp fuse within the wiring harness . none of them ever tripped

[TechMOGogy]

From EZ PowerSteering manual:
Must be at least 11.5v or the unit will switch off

[ExpeditionImports]

The EZ converter being supplied by the manufacturer (if purchased) is a 60A peak unit, and does not have any problem handling the installs that we have done with it. Considering the main power supply line is fused with a 40 amp fuse, I would tend to think that 40 is adequate. 90A should be more than enough....however the devil is in the details and I have never had a lot of faith in the converters especially if they are the budget models on the market.

Cheers,

Scott

[rmel]

A premiere power conversion company is Victron, Their 70A unit would do the job here
hands down. I even think I recall that unit being posted very early on this PS thread

Newfisher, what's the make and model of that 90A unit? I may have some working
knowledge about the manufacturer (in my day job I have to deal with some of these
companies--deal is putting it nicely ).

BTW you just might have a crappy connection or too high a voltage drop in your harness.
Your trusty Harbor Freight El Cheapo DVM is your friend

[Heinkeljb]

Don't forget converters have their own overheads. Which ever way you do the conversion! If you go from 12 to 24 then you increase the the current draw on the 12 volt side if you want to increase the current available on the 24 volt side.
Going the other way produces more heat for a bigger current draw on the 12 volt side with a smaller increase in current on the 24 volt side.

Unless the manufacture has a technical spec for the unit including a current draw graph, you will have to use measuring equipment to know what current / voltage changes there are in your installation. Most people will not have a suitable current measuring meter - but a quick look on line will produce something like this:-

http://www.tester.co.uk/chauvin-arnoux- ... AnJd8P8HAQ

Obviously the easiest way too measure the current being drawn.

John

[ExpeditionImports]

For those with the horn button blues with the EZ Powersteering. This is a direct fit, and solves the problem. It might also be of interest to those without the power steering as well.

Grant Part #5899 - Between $8-12 EVERYWHERE........ Also easily customizable as this is the button that is being used by vendors to put their custom logo in the center.

Cheers,

Scott

[NEWFISHER]

Awesome button find!

[Hotzenplotz]

thanks Scott

just ordered a button on ebay; saves me from drilling /grinding ...