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If you had an ammeter on the EPS, I'd bet it would be less than an amp at 30 mph and up.
Mike Dabrowski told me he put an ammeter on the EPS and measured currents as high as 20amps, but he didn't say under what conditions.

The EPS will only use as much power as it needs. Just like hydraulic power steering, the 'boost' is proportional to the load. If you are moving fast, there isn't much load on the steering shaft, so the boost is low.
Yes, and as I understand it there is no load if you are steering straight ahead? And does it draw current only to angle the front wheels, or does it continue to draw current to keep the wheels turned?

Low speed, you get the boost to help turn the wheels.
Still, I'm at a loss to figure out why Honda included it on the Insight-I when they went to such extreme lengths to save weight and conserve energy in other areas. And the fact remains that manual steering was perfectly adequate on many previous vehicles of even greater weight, plus the Insight-I's skinny tires shouldn't require a lot of effort to steer. Perhaps the EPS is lighter than a manual steering system?
 

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Ya know how if you are stopped and you turn the wheel, it will spring back a little when you let go? This is the residual "spring from the tires. If you turn the wheel and hold, it will take power to do that and the EPS would draw some current. Once you let go, the EPS power draw would go back down to nominal, or idle current draw.
Most power steering works on a torsion bar "like" system. If there is input at the wheel, and the tires are not aligned with that position, there is torque on the torsion bar in the steering system. The input and the output of the torsion bar are not equal. This difference is what gives the system something to amplify.
In hydraulic system, there is valving that directs fluid to one side or the other based on the input and output. To be honest, I don't know how the EPS works. Very similar I'd guess to how a servo works in RC. There's probably and input and output potentiometer on each end of the torsion bar. If there's a difference, it sends power to a motor to turn the wheels in that direction. When the 2 sensors match, there's no difference, so no power used (other than the idle power consumption of the circuitry.

BTW, I agree completely, the gen 1 insight is light enough it didn't need power steering. :) My '89 CRX Si doesn't have and it's pretty easy to turn except when totally stopped.
 

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For INFO:
The operating principle of the EPS is basically the same a hydraulic power steering except for the following:

A torque sensor mounted in the steeering box is used in place of the valve body.
An electric assist motor is used in place of the hydraulic power cylinder.
The EPS controle module is added.

The torque sensor senses the road/tire resistance and the turning direction of the steering wheel and sends a signal to the EPS module. Based on that signal and the "speed sensor" signal the EPS module determines the required current and sends that current to the EPS motor. Then the motor turns to move the steering rack right or left.

(I'm in the process now of mounting an Insight EPS steering box (rack and pinion) with module on my "dunebuggy". Will let you know how it works out.)
(I predict that within the next 5 years you will see most cars have switched over to the EPS instead of the hydraulic system.)

Willie
 

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I'm sure you've had enough feedback, but as a new owner I noticed the same thing. Turning on the A/C is like dropping an anchor. The a/c works great, but forces me to use lots of assist, and makes it harder to get into lean-burn. I ran the a/c on my ride home when I bought the car. 140 miles with the a/c set on econ at 78 degrees, and I still got around 65mpg.

It is sooooo much easier to drive this car correctly with the a/c off.

Regards,
 

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Would the situation be better if the AC were hooked to the 144v HV battery? Maybe this is how it's done in the HCH and the Prius??
Yeah for sure, hybrids allow all these compact motors.

Only thing is that its less efficient to drive the system that way than direct pulley drive but of course gives you more options when to run the AC and you have the compressor r un at its optimum speed rather than working in quite a large rpm range. Idle stop and solar top up to run AC when its parked occasionally aswell is why they seem to be going for it.

Also I think with some of the PHEV in fast charge that are liquid cooled but use the AC refrigerant to cool that circuit they may end up running the AC pump to cool the battery when its charging.
 

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I own a geo metro and man, you can feel it when the ac cycles on. I have wondered if a different pulley size would help or not since the vast rpm range it runs. It has manual steering,

Having said that, since I tinted the windows 20% rear 35% front realy helped to make it cooler and need less ac.

Infact I just did my front 2 windows 35% in my new insight and put a seconding coating of 35% film on the outside of the rear hatch.

Man, I use to run ac on the top speed, now half way is fine and cool.

You can find precut film online for about 50 bucks and its easy to install. If you tint it really dark and illegal, a cop has to find something else to pull you over and all you have to do is remove it. Man people in the show circuit just pay the ticket for the price of looking cool.

I did mines myself with film from walmart. 20% is really dark at night and can make it harder to parallel park. Forget the 5 or 2.5% stuff.
 

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i've noticed that setting the A/C on 75* and turnin the fan to 2 bars, gives a good combination of good mpg and comfort level. Since the a/c isnt set to 60, it cycles the compressor less ofter, letting the car in lean burn longer.

This is in 100 degree texas summers, where even setting it to 80 degrees, cools the car a little
 

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The AC is an mpg killer. I NEVER have it on at all, and just open windows by a couple of inches if reqd.

I don't live in Arizona though but in the fairly cool temperate climate of Northern England.

I'm an obsessive mpg nerd as well, and am happy to sweat in the name of fuel savings!
 
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