PTS Flowbench Forum

Yes me too, I was just wondering why you would want it any different.....?

Thanks for the replys Guys!
I really wanted to have one single control, as my goal is to eventually convert my bench to computer control / output.
Having a single control source is just one step closer.
Update:
I mounted another Harbor Freight Router Speed controller adjacent to the existing, and "tested" the set-up by first holding the controller in my hand to see if it was going to get hot, it didn't running three of the motors...

I'm posting this as I wait on the RTV to set-up for the last 3 motors installation...
Getting excited about how these Lamb motors are going to perform in my bench!

I purchased one of those Harbor Freight Dust Control Systems, as my shop is getting too dirty with metal filings. (My Corvette is really pissed off about all of the "head dander" getting all over her)

HEY! You need to buy a car cover for your Vette.

Ask Bruce if he is still producing the automatic speed controller. I bought one and depending what relay unit you use with it you could control all of your motors. When I am done I will do 4 motors at a time. With Bruce's speed controller it automatically maintains your test pressure to what you set it at.

Do you still do those Bruce?

John

UPDATE:
Ran the bench with a head on it:
All 6 motors running full speed
31" WC with valves closed
27.5" WC at 0.050" Intake valve open
20.875"WC at 0.35" and up intake valve openings.



I was very surprised at the voltage readings:
Not much difference between the readings at 10"wc!!!!

If you want to run more than one motor on a speed control you need to look at getting a solid state relay and phase angle control module of suitable voltage/amp rating to match your motors.

My PTS manual/automatic speed control then hooks up to that. I do not have it listed on my website yet but can make them.

Update:
I ran a separate extension cord from the basement, and plugged the two lower motors in directly.
Now, each of the Harbor Freight Speed controllers are running 2 motors each.
Turned off all lights (sans 1) and now the bench pulls 33"wc valves closed.

I'm wondering if my design is what is holding me back here.
Here's the flow path: (starting from the head):
Head adapter
Bore adapter
MAF (at the bottom of the MAF is where the manometer connects)
12" x 12" x 31" plenum (I call this the MAF Plenum)
on the RH side of the MAF Plenum is a 4" opening into the Vacuum Source Plenum.
The Vacuum Source Plenum measures 12" x 12" x 48".

Will I get any increase in water column if I duct from the MAF directly to the vacuum source?
Will I get any increase in water column if I decrease the volume the vacuum source plenum?

UPDATE:
Added a duct from the MAF directly to the Vacuum Source Plenum.
Absolutely no change.

Put dividers between the vacuum motors to prevent air from one motor output air affecting the adjacent motor.
No Change...

Guess I have to add more motors...

6 motors should be more than enough. I can pull 400+ cfm @ 28" with 6 surplus motors. We need some more motor info and maybe a drawing with sizes through the bench. 33" with valves closed sounds like a leak especially with 6 motors running. All motors running eliminates the leak through the motors. Check the pickup connections too.

Everything is Sealed!
I traced with my velocity probe around all of the joints. No indications of leaks anywhere!
The specs on these motors were supposed to be 98 cfm @100"wc. - I'm nowhere even close to that!
The highest MAF reading with the valve open on the head is 3.200 vdc, which equals 231 cfm at 21"wc...
Maximum Manometer reading is still 33" wc with valves closed...


I took the motor off of one of my shop vacs, looks almost identical to the Lamb motors.
So I installed it at the top of the Vacuum Source Chamber...
Waiting for the sealant to cure, we'll see what effect the added motor has...

S2Z wrote: The specs on these motors were supposed to be 98 cfm @100"wc. - I'm nowhere even close to that!

Maybe 98cfm max at full flow and 100" at no flow but I doubt 98cfm@100" flow sorry to say. What model Lamb motors?

What I have found is looking at motor charts is to look at the max depression you need to pull ie; test pressure + delta P pressure add these together look at your motor chart to find the CFM at that pressure and that is what your motors will flow in a bench. Multiply this number by the number of motors or divide max bench CFM desired by this CFM and it gives you a good idea of flow capacity or motors required.

On the PTS bench testing at 28" using my DM which works on a 16" Delta P you are looking at a total of 44", so any motors you spec for my bench you look on the motor for 44" and read the rated CFM for an approximation of capacity. It holds out close but not exact . . .