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snwcmpr
12/07/2019 9:29 AM
roar

snwcmpr
11/27/2019 11:44 AM
greenman

allenb
11/27/2019 11:04 AM
Nice! I know Netrix is going through things and tweaking as he see's issues

snwcmpr
11/26/2019 1:35 PM
I got an email that I had a PM. So, that is working for me again. greenman

snwcmpr
11/26/2019 1:33 PM
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How to control a fluidbed roast profile?
Dan
Personally, I would just get another Fuji PID, but with the right outputs, and save the other one for some SSR controlled project rather than add complexity.
1 pound electric sample roaster, 3 pound direct-flame roaster, both handmade; modified Mazzer Mini grinder, LaSpaziale Vivaldi II automatic espresso machine. When the electricity goes out I make vacpot coffee from beans ground on my Zassenhaus hand grinder, and heat the water with a teakettle on the gas range.
 
http://www.intactamerica.org
oldgearhead
Humm, after reading the data sheet I think the problem is not the control signal, it clearly states 0-10VDC, but the max pressure of 100 psi (AO). The reason I say that is often valves of this type require a minimum pressure to start opening. With so high a max pressure, maybe the min pressure is too high.
Have you tried it with pressure on the input?
The "for pressures less than 10 psi, consult the factory" statement is a big hint.
No oil on my beans...
 
Dan
Some valves have a spring to make sure the valve always closes. This means that they have a "break" pressure to achieve. This is just another way of saying what OGH is saying.

However, I don't think that's the case here. The specs say the pressure range is -5-100 psi. A valve with no break pressure is often spec'd as, say, 0-100 psi. Tamarian's valve will even open if there is a slight vacuum on the inlet side. Therefore, this valve should be opening even at ambient pressure, which is what you have been trying to do.
Edited by Dan on 06/24/2013 10:22 AM
1 pound electric sample roaster, 3 pound direct-flame roaster, both handmade; modified Mazzer Mini grinder, LaSpaziale Vivaldi II automatic espresso machine. When the electricity goes out I make vacpot coffee from beans ground on my Zassenhaus hand grinder, and heat the water with a teakettle on the gas range.
 
http://www.intactamerica.org
allenb
I've got what should be an identical valve by Kelly Pneumatics I'm still experimenting with. At 10 volts from my DC power supply I'm pulling around 190 mA which makes sense with the valve's coil having a resistance of 54 ohms.

The PXG data sheet shows the 0-10 V output should not be applied to any load less than 10 kohm and according to a controls rep I spoke to today the PXG cannot supply anywhere near the current needed to open the valve.

[4] Voltage output (0 to 5 V DC/1 to 5 V
DC/0 to 10 V DC/2 to 10 V DC)
• Accuracy: ± 5%FS
• Linearity: ± 5%FS
• Load resistance: 10 kohm MIN

Clippard and Kelly make a driver board for this purpose which interfaces the control signals from most PID controllers and outputs the higher currents needed to drive the valve

http://www.kpiweb...rvBrd.html

When I heard you were planning on driving the valve with your Fuji I didn't know that it's 0-10V output would be a problem either.

Another option is to build your own for very little $. I've been working with Stan (rustic_roaster) on various control scenarios for this valve and he's got a design or two for a driver board that may work for you.

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
rustic_roaster
tamarian wrote:

Dan: No, not sure, just know what I ordered :) The order option offered a range of VDC 0-5 or 0-10VDC, the documents online refers to VDC as well: http://www.clippard.com/downloads/PDF_Documents/Product%20Data%20Sheets/EVP_Proportional_Valve_Data_Sheet.pdf

My Fuji PXG4, output2, can send 0-5 / 1-5 / 0-10 / 2-10VDC

OGH: Here's the part number: EV-P-10-25A0 and yes, it's the 0-10V DC, and it supports air and gas, according to docs.

Online support replied with "The EVP is a current based valve, 4-20Ma". and referred me to a distributor, so I re-sending the enquiry to them.


Tamarian,

As Allen mentioned it is possible to build a module that works like the Clippard EVP driver module for less money, but I think you need to determine if the valve you have is working.

I suspect the Online support person might of thought you were using the clippard valve driver module to interface the EVP valve. I think there is way to use that module to convert a 4-20mA signal into a higher current drive for the valve.

According to the datasheet and the tests Allen has run the valve works from current not voltage. I think his tests were close to the datasheet, maybe needing a little more current to open. According to the datasheet you need 70mA to get the valve to start to open.

I seen you put 9V across the valve and nothing happened, also comments that the wire did not look like polarity was identified. Did you try reversing the leads?

One other quick test you can do is to measure the DC resistance of the valve and confirm it is about 54 ohms. If it is not then the valve is not the EPV valve in the datasheet or is faulty.

If you measure the current with a ammeter when the 9V is applied that might also help to identify if the input circuit is functional. You might also want to measure the voltage across the leads to make sure the 9V supply is not droopping causing lower current.

If the DC resistance is OK and the current reflect V/54 then that would suggest the valve is faulty.
 
tamarian
Thanks for all the input Allen, Dan, OGH, RR

When I hook the valve to a standard 9V battery, I expect the current to be voltage/resistance (9/54) = 0.167 amps, or 167mA. That is more than enough to open the valve, but maybe tenough to cause damage? Is the math correct, or is it no where near enough to reach 4-20mA?

Tried it again, and there seem to be a tiny minute flow of gas. Got my ear close to the valve, and there is a tiny tic sound with initial wire contact to battery, same when reversing polarity.
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
rustic_roaster
tamarian wrote:

Thanks for all the input Allen, Dan, OGH, RR

When I hook the valve to a standard 9V battery, I expect the current to be voltage/resistance (9/54) = 0.167 amps, or 167mA. That is more than enough to open the valve, but maybe tenough to cause damage? Is the math correct, or is it no where near enough to reach 4-20mA?

Tried it again, and there seem to be a tiny minute flow of gas. Got my ear close to the valve, and there is a tiny tic sound with initial wire contact to battery, same when reversing polarity.




Seem like the valve may be functional. Did you measure the battery voltage and resistance of the valve?

You will only get 176mA when the battery is 9V, if it was not fresh or was connected to the valve for a while it might be less than 9V. At 7V you will only have 130mA.

I dont know if Allen's valve is the same part as your's or not
but Allen's valve required 90mA of current to get gas to start to trickle flowing in his setup.

One thing I noticed on the datasheet is the -A0 section of the part number. Is that for Max pressure or the amount of pressure used to calibrate the valve. Not sure if that means the valve might not work the same if you dont have that much pressure.

* Note: The EVP Proportional Valve can be calibrated for pressures less than the maximum shown here. Lower pressures may be
substituted, and will be used for calibration. The pressures shown above are standard options. For pressures less than 10 psig,
please consult factory.
 
Dan
This valve has a very small orifice, so you might not hear air coming through it. Best to hook it up to, say, a 30 psi air line when testing.
1 pound electric sample roaster, 3 pound direct-flame roaster, both handmade; modified Mazzer Mini grinder, LaSpaziale Vivaldi II automatic espresso machine. When the electricity goes out I make vacpot coffee from beans ground on my Zassenhaus hand grinder, and heat the water with a teakettle on the gas range.
 
http://www.intactamerica.org
tamarian
[Seem like the valve may be functional. Did you measure the battery voltage and resistance of the valve?

You will only get 176mA when the battery is 9V, if it was not fresh or was connected to the valve for a while it might be less than 9V. At 7V you will only have 130mA.

I dont know if Allen's valve is the same part as your's or not
but Allen's valve required 90mA of current to get gas to start to trickle flowing in his setup.

One thing I noticed on the datasheet is the -A0 section of the part number. Is that for Max pressure or the amount of pressure used to calibrate the valve. Not sure if that means the valve might not work the same if you dont have that much pressure.

* Note: The EVP Proportional Valve can be calibrated for pressures less than the maximum shown here. Lower pressures may be
substituted, and will be used for calibration. The pressures shown above are standard options. For pressures less than 10 psig,
please consult factory.


Need to get a fuse to use my multimeter :) But the 9V battery was fresh/new. So it should be way more than 4-20mA. The -A0 part of the part number is for the seal type.

Still waiting for a reply from Clippard/distributor, as I pointed to them that I ordered the 10VDC model, and referencing their spec sheet that the input is VDC, etc. Maybe they assumed I got the driver board.
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
allenb
Dan wrote:

This valve has a very small orifice, so you might not hear air coming through it. Best to hook it up to, say, a 30 psi air line when testing.


Dan makes a great point. The flow through a .009” orifice is extremely small and I could barely hear the flow through mine at full flow. The volume of propane through a small burner as we’re using with a 1 or 2 lb roaster is much less than most of us imagine.
I’m assuming you calculated the flow in liters per minute needed for your burner to reach the necessary btu’s/hr for your roaster and used this for sizing the valve’s orifice size. The way to test if the valve is functioning is to pipe it up to your burner and measure the pressure in between your valve and the burner. If the valve’s orifice is sized to work with your burner’s maximum needed flow rate then you will see the proper maximum pressure displayed on your gauge when you vary the dc volts from the voltage needed to start opening the valve through 10 vdc. It’s very important to maintain the minimum needed pressure differential across the valve to allow achieving the needed liters per minute. In my case I needed to maintain at least 45 psi input to the valve to achieve 30 psi at the burner’s orifice at maximum output.
Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
rustic_roaster
tamarian wrote:


Need to get a fuse to use my multimeter :) But the 9V battery was fresh/new. So it should be way more than 4-20mA. The -A0 part of the part number is for the seal type.

Still waiting for a reply from Clippard/distributor, as I pointed to them that I ordered the 10VDC model, and referencing their spec sheet that the input is VDC, etc. Maybe they assumed I got the driver board.


Assuming they sent the correct part that matches the datasheet you linked, I think you should forget about the valve working directly from 4-20mA.

According to the datasheet -A0 is the max pressure identifier = 100psig. Seal type is identified as blank,E,V

A fresh 9V battery will last about 2 or 3 hours for that valve. I am sure it gave enough current to start with but if you left it connected for a while it might not be fresh any longer. Getting a fuse for your DMM will be useful.
 
tamarian
A fresh 9V battery will last about 2 or 3 hours for that valve. I am sure it gave enough current to start with but if you left it connected for a while it might not be fresh any longer. Getting a fuse for your DMM will be useful.


The 9V was just for testing. The valve will be run, if all goes well, from my Fuji PXG4, whose output 2 is VDC, selectable from 0-5 / 1-5 / 0-10 / 2-10VDC1.

The next test is for input pressure, and locating a gas supplier locally who can fill up a tank at that pressure.
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
tamarian
allenb wrote:

Dan wrote:

This valve has a very small orifice, so you might not hear air coming through it. Best to hook it up to, say, a 30 psi air line when testing.


Dan makes a great point. The flow through a .009” orifice is extremely small and I could barely hear the flow through mine at full flow. The volume of propane through a small burner as we’re using with a 1 or 2 lb roaster is much less than most of us imagine.
I’m assuming you calculated the flow in liters per minute needed for your burner to reach the necessary btu’s/hr for your roaster and used this for sizing the valve’s orifice size. The way to test if the valve is functioning is to pipe it up to your burner and measure the pressure in between your valve and the burner. If the valve’s orifice is sized to work with your burner’s maximum needed flow rate then you will see the proper maximum pressure displayed on your gauge when you vary the dc volts from the voltage needed to start opening the valve through 10 vdc. It’s very important to maintain the minimum needed pressure differential across the valve to allow achieving the needed liters per minute. In my case I needed to maintain at least 45 psi input to the valve to achieve 30 psi at the burner’s orifice at maximum output.
Allen


I selected the 0.025" orifice, for maximum flow. I'm totally new to gas, and looks like I'll have to dig around to find suppliers who can fill tanks to these pressures. When you first mentioned this pressure differential I got two gauges to put one before and after the valve. First tank I tried didn't even register any move on the gauge.

But need to hook up some contraptions to work the valve with a cycling pump just to make sure the valve is working with some reasonable pressure, and no faulty.
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
allenb
tamarian wrote:

A fresh 9V battery will last about 2 or 3 hours for that valve. I am sure it gave enough current to start with but if you left it connected for a while it might not be fresh any longer. Getting a fuse for your DMM will be useful.


The 9V was just for testing. The valve will be run, if all goes well, from my Fuji PXG4, whose output 2 is VDC, selectable from 0-5 / 1-5 / 0-10 / 2-10VDC1.

The next test is for input pressure, and locating a gas supplier locally who can fill up a tank at that pressure.


According to the Fuji rep I recently spoke to you should not try and control the valve from the PXG's 0-10 output directly as it's not meant for loads under 10,000 ohms and is not capable of anywhere near the current needed. The PXG needs an interface between it and the valve to produce the current needed to drive it.

I've been told the driver is around $70.00 plus shipping for the Kelly Pneumatics version.

I'm not following what you're saying about filling up a tank at a certain pressure? Liquified propane maintains a temperature/pressure relationship on it's own and at room temperature will be over 100 psi at 75 F. You'll need a high pressure gas regulator to take it down to the pressure you'll be sending to the valve.

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
tamarian
According to the Fuji rep I recently spoke to you should not try and control the valve from the PXG's 0-10 output directly as it's not meant for loads under 10,000 ohms and is not capable of anywhere near the current needed. The PXG needs an interface between it and the valve to produce the current needed to drive it.

I've been told the driver is around $70.00 plus shipping for the Kelly Pneumatics version.


Not sure who to listen to, Fuji, Clippard, distributor, etc. Specs say 0-10VDC, via email, they say it needs 4-20mA. None of them in synch with (Current = Volts/Resistance). But I ordered the 0-10VDC to 0-20mA converter, just to have all possibilities available.

I'm not following what you're saying about filling up a tank at a certain pressure? Liquified propane maintains a temperature/pressure relationship on it's own and at room temperature will be over 100 psi at 75 F. You'll need a high pressure gas regulator to take it down to the pressure you'll be sending to the valve.


Meant to just test with air from a inflator pump with gauge, just to get the valve to open fully with 9V battery and pass the air. Initially tested with natural gas tank I had, wasn't enough pressure to open it. I have yet to know how much pressure I tested with, so I need to eliminate this factor, enough pressure.

Based on specs, 9V should be good enough voltage. Based on email, 100+mA from the 9V battery should be enough as well. So it remains to ensure enough pressure is present when hooked to 9V battery. If the valve is functional, next step is to test for fine control, and what will work correctly, VDC or current via converter.

I hope my posts aren't sounding too agitated. I'm actually thrilled with the possibility of getting this to work, just trying to absorb lots of new and sometimes contradicting info. We'll get there. Can't wait to see what you guys are working on!
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
allenb
Looks like you’re heading in the right direction for getting things figured out. I know how the 0-10 dc, 4-20 mA control modes can be confusing and it stumps even the folks who work in controls half the time.

The thing to remember is the valve works by a variable current being applied to its coil and this is what raises and lowers the armature. Varying the voltage (0-10 vdc) into a 54 ohm coil causes the current to vary from 0 to 200 mA.
The PID controllers output modes (4-20 mA, 0-5, 0-10 dc etc.) are for control purposes only and not intended for powering a valve’s coil. You will definitely need a driver between the Fuji and valve and the driver looks like it can accept either 4-20 or 0-10 control modes.

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
tamarian
allenb wrote:
You will definitely need a driver between the Fuji and valve and the driver looks like it can accept either 4-20 or 0-10 control modes.


You mean a converter won't work? This is the one I ordered: http://controlsce...fault.aspx
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
allenb
tamarian wrote:

allenb wrote:
You will definitely need a driver between the Fuji and valve and the driver looks like it can accept either 4-20 or 0-10 control modes.


You mean a converter won't work? This is the one I ordered: http://controlsce...fault.aspx


What would be the purpose of having the 4-20 mA option? I'm assuming you're not looking to try and power the valve's coil with this?

Allen
1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
 
tamarian
allenb wrote:

tamarian wrote:

allenb wrote:
You will definitely need a driver between the Fuji and valve and the driver looks like it can accept either 4-20 or 0-10 control modes.


You mean a converter won't work? This is the one I ordered: http://controlsce...fault.aspx


What would be the purpose of having the 4-20 mA option? I'm assuming you're not looking to try and power the valve's coil with this?

Allen


The valve is powered and controlled by a control signal. The confusion is whether it is a 0-10VDC signal or a 0-20mA current signal, that is yet to be answered/clarified by Clippard. If it's a VDC input signal, that's a match with Fuji's VDC output signal. If it's a current signal 0-20mA, then a signal converter/transducer taking 0-10VDC signal and converting it to a 0-20mA signal should work.

Is it not the same as a driver taking a 0-10VDC signal and outputting 0-20mA signal?
Wa'il. 1 Kg PID'ed gas-fired fluid bed roaster, GS/3MPS, K10F
 
http://english.varietalcafe.com
oldgearhead
I think the problem is your Fuji's output is a 0-10V control signal,
and the Clippard requires a 0-10V transmitter. The one you have ordered might work for you if you connect the 4-20ma signal across a 1/2 watt, 500 ohm resistor. However, if it doesn't this one will:

http://www.jhtech...eable.html
No oil on my beans...
 
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