My 80amp SCR Motor Controller

[cspeier]

I was told I could mount it either direction, is this incorrect?

[49-1183904562]

Chad,

Heat normally rises so yes vanes vertically is the best installation so the excess heat would normally flow upward taking in cooler air from the bottom. If you could put a small muffin fan on the current installation that would work too and eliminate any future overheating issues.

Rick

[cspeier]

OK, I have been using this all day and have an issue. The head I'm working with flows 315 at .800 at 28" on my old bench. I can pull 35" at the same lift with the bowl all the way open.

The old bench has a 3.100 square hole orifice plate. Basically the largest in my orifice plate. For the last 4-5 years, I've flowed everything on that orifice. It's a crude hole!

My cd on that hole is .600

OK, now my new bench. I have that same head on the new bench. I have two plates from Bruce. One is 2.200 diameter, 350 cfm (.575 cd). The other is 2.500 diameter, 450 cfm (.580 cd). I calibrated both with another sharp edge from Bruce.

Now my problem. The fixture was taken off the old bench and the head was flowed on the new bench. I knew all along my motors were weak, but that is an easy fix. The bench with the 2.300 plate would only pull 20" at .800. I looked for leaks and such and everything looked good. I decided to flow it with the 2.500 plate. To my surprise it pulled 24" at .800. I picked up 4" with .300 hole diameter.

So my question. What the heck is this telling me?? My brain tells me to put in a 3.100 hole like my old bench and it will pull 35".. HELP!!

Also, I have some slide plate leakage on the exhaust side. Is this normal??

[bruce]

Are you inputting the orifice diameter in the FP1?

I'm not familiar with using the FP1 with various size orifice plates.

I do not see any leakage on my slider plate and have not heard back from anyone else having any concerns about this. It is quite possible though as each flowbench build is going to be different based on how it's assembled.

[cspeier]

Yes Bruce I enter the hole diameter.

Yes it leaks pretty good. However, I had the small orifice hole and not sure what the depression was because I was looking for leaks. It very well may have been 40-50"..

[bruce]

[cspeier]

Guys, tell me if my thinking is correct.

I have a 36" Dwyer manometer. I connected it to the top cabinet hookup to confirm my depression. My processor said 20" and the manomter as well. Although the manometer was a little bouncy...

Then I hooked it to the bottom hookup and the manometer showed 30".. Is this telling me I have a 10" Delta P??

Also, I put the processor in manometer mode. This is what it showed. Is this correct?

20.02 10.5

Which I know the 20.02 is depression
But what is the 10.5 number??

FYI, I changed this. I had the FP PS3 emabled. So, I see that it's also showing 10"+ across the plate..

[bruce]

Run your bench at various static pressures and verify the digital manometer is reading the same as your water gauge. This will verify it is linear across the sensor. You would only hook up the - side and run it in manometer mode.

If you hookup the -/+ to the CFM sensor and put it in manometer mode you are seeing the differential pressure in " H2O across the plate.

[cspeier]

OK, I made me a 3.100 square hole and on that same head I can now pull 29".. I need better motors. However, I found an issue. I have a sharp edge plate and it's a small hole (113 cfm). I can run that right up to 40 inches. At 28" it's steady as a rock while calibrating the square hole. Then I go and put my sharp edge 2.250 hole (356 cfm) and I can not pull 28". I can get it to 26" and that's it. Again, motors. The problem is it's really bouncy on the cfm readings. Like 348-355'ish. It's bad.

One, what could cause this? manometer pickup placement? Delta P wrong? I have 5" across the orifice with the 3.100 hole. Should I try a in line dampener?

Two, what is the best way to check for leakage? With the head and fixture, holding the valve shut, with the 3.100 hole, the FP reads less than 10 cfm. I'm thinking that is OK but not sure. So, how do you recommend checking the cabinet?

PS. I had it running full bore today for 12 minutes and I could touch the SCR. However, on the exhaust side, I do have leakage at 28".

[bruce]

First off did you see if your manometer sensors are linear as compared to your water gauge?

If you close off the top hole and run the bench up SLOWLY in static pressure and you see CFM you have a leak in the plenum area somewhere. With the bench sealed up you should have no flow.

[bruce]

Bouncing numbers can be averaged out or sample rates can be changed. Someone else with an FP1 will have to comment on this as I do not have one here that works with an orifice bench.

[cspeier]

The digtal and water manometer are the same. The depression is rock steady. The 2.500 sharp edge orifice is rock steady. However, the hole I made is really turbulant.

Both benches read different

I need a large sharp hole made and better motors.

Also, with the hole blocked off I show zero leakage, then it picks something up, maybe 2-3 cfm and then it goes back to zero. However, more zeros that numbers.

I have some issues to work out and I have old faithfull on stand by!

[msj442]

is old faithful of the msd internal design? how many motors in there and what kind. you were pulling good depression if i remember reading correctly.

max

[cspeier]

[bruce]

I'm wondering how much of an effect the SCR is having on max output of your motors?

I know with the HF or Payne control you don't get full output from the controlled motors.

Since you are controlling all the motors is it dropping the max output?