Dexter E/H Actuator

[Buttercup]

Does anybody have any experience with Dexters E/H Brake Actuator? I have been looking into this topic for some time (as some may know) and am putting together a comparison of the different actuators out there - and there are a few.
But on this forum I don't see very many people talking about Dexter actuators. So if you have one and can offer comment I would appreciate it.

T & K

[Janets Husband]

Originally Posted by Buttercup

Does anybody have any experience with Dexters E/H Brake Actuator? I have been looking into this topic for some time (as some may know) and am putting together a comparison of the different actuators out there - and there are a few.
But on this forum I don't see very many people talking about Dexter actuators. So if you have one and can offer comment I would appreciate it.

T & K

Sounds like a worth while pursuit, One specification I find hard to come up with is the "Delay Time" the time between when the actuator gets the electrical signal, to the time the pump starts and applies the hydraulic brakes.
Keep up the quest.

[markdoane]

I didn't know Dexter had an E/H unit. Good Find! Do you know how long it has been available?

The instruction manual is dated 5/05.

I agree with Gary. Delay time (to full pressure) would be very useful information.

[Inland RV Center, In]

There are several factors and features that differ from one Actuator to the next, other that rise time.

I would suggest a comparison be made against the Actibrake, which has the following specs.

1. Fluid reservoir--- 650 ml, (36 cubic inches) 260 % larger than the most
popular competitor.
2. Number of pistons--- six
3. Kind of pump---rotary
4. Number of pump stages---two
5. Number of pump circuits---two
6. Maximum pressure---1400 psi
7. Response time to maximum pressure---.79 (point79) seconds
8. Extend a hold feature---yes
9. Design--- Built and tested to SAE-J1455 standards
10. Exterior cover---sealed against moisture
11. Size---8.75"high, 10.5" long, 4.25" wide
12. Weight---13 pounds

Andy

[markdoane]

Andy,

I have a question about the Acti-brake actuator. How can the pump be a rotary pump and a piston pump at the same time? Is it like a rotary piston engine in an airplane?

Inquiring minds want to know.

[Mike B]

Don,
Perhaps the pump is a vane type pump, similar to a Roots type blower on a Detroit diesel. They may call the vanes (3 on each side) pistons. Back when I was pulling food grade tankers we had a pump that was a vane type pump made by a company named Drum for pumping liquids. It worked with everthing from heavy sugarcane molasses to hot thin liquid sugar.You just varied the rpm's depending on the thickness of the product.
Mike B

[Buttercup]

I think it is more like the attached picture.... Imagine 6 pistons instead of 2. One thing that concerns me about the Actibrake is that it does have so many more moving parts than a standard actuator - more to go wrong.

But I do like the fact that it will keep on pumping no matter what, like if there is a leak the brakes will not fade away as quickly because the pump keeps on pumping. At least it keeps on pumping until the hold feature kicks in and then the motor stops and a valve closes holding pressure on the system.

I found the dexter doing a google search for electro-hydraulic. I did find a few others but none that I liked well. Being as Dexter is a fairly known brand name I gave it more of a look than some of the others I found.

[Buttercup]

I put together a little comparison chart based on the information I was able to find (and what was provided) between the Dexter and Actibrake. What information I couldn't find I left as unknown hoping that I can eventually find the info or somebody will provide it.

As a personal note on doing research - both web sites had surprisingly little information on the product specifications - a big disappointment. But both had posted the manual as a PDF file. Actibrake is practically nonexistent as a search item on Google and almost no information is available on the company while Dexter is a well known company. None of that matters when making a decision about an actuator of course.

Actibrake erroneously states that they have the largest fluid reservoir in the industry which is not the case. I can't verify response time of the Dexter but can't imagine that it is all that much faster or slower then the Actibrake.

After all of this research I am still undecided. I trust the Dexter name but I do like the extend a hold feature of the Actibrake. It doesn't matter to me how many pistons an actuator has or how many “circuits” it has – if the pump goes bad, it goes bad. It becomes a matter of how many moving parts are you comfortable with. Dexter's unit is all solid state – Actibrake's had solenoids and a relay. Again, 6 of one, ½ dozen of the other.

I would like to know how much the Actibrake is including shipping???

I published the comparison on my web site because I couldn't get it to display properly on the forum. CLICK HERE to see the comparison.

[markdoane]

I like the chart. The other two units that I have heard of are the Masterbrake Elecdraulic http://www.masterbrake.com/ and the Carlisle Hydrastar http://www.carlislebrake.com/spec_hydrastar.html

I'm not making a recommendation, just filling out the list in case someone else is looking.

Good call on the wobble plate. I did some research and also found:
radial piston pump
swashplate pump (different than a wobble plate)
bent axis pump

[Inland RV Center, In]

Markdoane.

I submitted Actibrakes published information.


Buttercup.

Shipping costs depend on a zone. Therefore shipping costs can only be determined when you know the sender and the receiver.

As with anything, depending on several business situations, the selling price varies.

We are not permitted to post selling prices, except wide "ball parks".

You can however, determine many of our prices by going to the parts section of our web site, www.inlandrv.com

Andy

[Buttercup]

Andy,

I did check the web site and I only see where the actuator is part of a kit - it is not listed individually so it is hard to guess the price. I also attempted to search other web sites with the same results. A ball park price for the unit itself without shipping would be helpful. Is it greater or less than Dexter's price?

markdoane,

I have found the information on the other controllers and I will add that to the comparison just for good measure. My original post was about Dexter's unit because I had not heard that it even existed. These units are popping up everywhere as I search the web. Please - make it stop!!

[Buttercup]

I updated the information on the web for the EH Comparison Chart. It can be seen HERE.

Bottom line is that Dexter's response time has been posted - 0.5 seconds. Also I have info about the pump type and motor duty cycle.

[Inland RV Center, In]

Buttercup

The Actibrake actuator is our part # 86400.

It is listed and pictured in the sale parts section of our web site.

Andy

[Anon]

One of the options I had mulled over was getting the disc brakes. I had it all priced out by Axis but decided that with the size of the trailer and the size of my pocketbook I should go with the drum brakes. I do like the disc brakes but it meant whether or not I got a new axle. I would rather have new drim brakes than no brakes at all.
I have my quote somewhere around here. If you need to know exactly what the part number and/or the price was let know. I am sure I can dig through my stack of trailer stuff that the wife has made for me in the den!

[Buttercup]

Andy,

Thanks - found it. Now I see why I missed it. I searched using the term "actibrake". If I had used the term "actuator" I would have found it right away.

tk

[Janets Husband]

Ok

I know I'll get flamed for this but, what is with the delay time for actuation for disc brakes?
I have been told by people on this forum that disc brakes are the only way to go. I say, I'm not so sure about that.

Let's do a little fancy foot work.
If your speed is 65MPH you are traveling at 95.3 feet per second.
If your brakes take 0.7 seconds to actuate then you have gone 66.71 feet.
You have just traveled about 2 times the length of your rig before the trailer brakes are fully available to help you stop.

Is this a good thing, appearently the manufacturers have be able to sell the idea.
Will there be a instance when these brakes will fail you when you need them?
Sounds like they are not there the instant you need them.

I like the old brakes, they work the instant you apply them.

[Buttercup]

AAhhh,

You forgot to integrate the amount of deceleration (or negative acceleration) into your equation. The vehicle & TT are in the process of stopping by the braking action of the car and the increasing braking action of the TT while waiting for the brakes to come up to pressure.

Also, that response time is from zero to full brake pressure. Actual total response time to proportionally apply the brakes will depend on how much brake you apply and the response characteristics of your brake controller and actuator.

[Inland RV Center, In]

Janet's Husband

The automotive industry certainly has far more resources at it's finger tips than any RV manufacturer.

If disc brakes were not superior, why have so many auto manufacturers gone to them?

The bottom line is that they are very superior, especially to electric brakes.

If you consider how many things can go wrong with electric brakes over the disc brakes, the disc brake systems will win that argument , hands down, every time.

Then when you consider the cost of repairs, again the discs win, every time.

Anything that's made by man, can fail. It's the failure rate that becomes the key. Disc brakes, simply because of fewer parts, have a far less failure rate than electric brakes.

Finished diamonds can crack. And the kids we men make? Another story.

The key words are "proper and routine care", just like we do for kids. That does not gaurantee zero failure, but it does reduce the probability.

Andy