Help with Profilux 4 and air temp/humidity control

Laith · Apr 23, 2021

I need some help/clarification regarding a specific use of the Profilux 4 (P4).

I have an exhaust fan that vents air from above my DT directly through the wall above the DT to the outside. The fan speed on this fan is controllable via a 0-10v connection which I have made to the P4 through a GHL breakout box.

I also have a GHL air temperature and humidity sensor situated above the DT.

I want the exhaust fan to run continuously 24/7 at a low speed (let's say about 10-20%) to vent air from above the DT to the outside. Then I would like the P4 to ramp up that speed based on the air temperature and/or humidity levels that the air temp/humidity sensor is reading. So my questions to any Profilux gurus (@Lasse for example

) :

How do I do this (have a minimum fan speed 24/7 and then ramp up and down from there)?

I tried setting the v settings on the 1-10v setting interface to min 2, 3 and 4v max 10v, thinking that this would force the exhaust fan to always receive 2,3, or 4v and therefore for it to run all the time. I don't think that this can be used like this as sometimes I'm seeing 0v being sent to the fan when for example the temp or humidity reading is not high enough to trigger fan on...

I currently use the two position controller setting in the sensor settings and I'm guessing that one of the Pause/Pulse options may work in this way but I cannot figure out how these other options could work for me because they seem to just delay on/off switching by a set time (yes, I've read the manuals)...

Help? ;Wideyed

MnFish1 · Apr 23, 2021

Laith said:
I need some help/clarification regarding a specific use of the Profilux 4 (P4).

I have an exhaust fan that vents air from above my DT directly through the wall above the DT to the outside. The fan speed on this fan is controllable via a 0-10v connection which I have made to the P4 through a GHL breakout box.

I also have a GHL air temperature and humidity sensor situated above the DT.

I want the exhaust fan to run continuously 24/7 at a low speed (let's say about 10-20%) to vent air from above the DT to the outside. Then I would like the P4 to ramp up that speed based on the air temperature and/or humidity levels that the air temp/humidity sensor is reading. So my questions to any Profilux gurus (@Lasse for example ) :

How do I do this (have a minimum fan speed 24/7 and then ramp up and down from there)?

I tried setting the v settings on the 1-10v setting interface to min 2, 3 and 4v max 10v, thinking that this would force the exhaust fan to always receive 2,3, or 4v and therefore for it to run all the time. I don't think that this can be used like this as sometimes I'm seeing 0v being sent to the fan when for example the temp or humidity reading is not high enough to trigger fan on...

I currently use the two position controller setting in the sensor settings and I'm guessing that one of the Pause/Pulse options may work in this way but I cannot figure out how these other options could work for me because they seem to just delay on/off switching by a set time (yes, I've read the manuals)...

Help? ;Wideyed

Curious - I had a set up like this. If the air and temp sensors do not register enough humidity, temperature, what is the problem with having the fan off? Isn't that the purpose of the sensors?

Lasse · Apr 23, 2021

This can´t be done directly out of the box as I see it.

However with a little DIY - it can be done. You need a switching 12 V relay, an ADIN expansion card, 2 L (1-10 V) outlet - let us say L1 and L2. A switch outlet,a 12 V PSU, a propeller control for 12 V and a 12 V exhaust fan and an illumination channel. If you want to go further with this - I can comeback with my ideas. And it is only possible to manage the temperature this way - the humidity cant be used for a 1-10 control signal as it is now

Sincerely Lasse

Laith · Apr 23, 2021

MnFish1 said:
Curious - I had a set up like this. If the air and temp sensors do not register enough humidity, temperature, what is the problem with having the fan off? Isn't that the purpose of the sensors?

That's a good question.

Here's the issue. The exhaust fan can only be controlled by either the air temp sensor or the humidity sensor (in theory any of the sensors but only one, not multiple ones).

Higher air temp doesn't always equal higher humidity and vice versa. So if I set the 1-10v channel to the air temp sensor it might not turn the fan on because the air temp is not high... but the humidity might be at 65 or 70. And the humidity can be 50 or 55 and the the air temp can be 31 or 32.

I hope that by keeping the fan running at low speed all the time this would solve this issue.

Laith · Apr 23, 2021

Lasse said:
This can´t be done directly out of the box as I see it.

However with a little DIY - it can be done. You need a switching 12 V relay, an ADIN expansion card, 2 L (1-10 V) outlet - let us say L1 and L2. A switch outlet,a 12 V PSU, a propeller control for 12 V and a 12 V exhaust fan and an illumination channel. If you want to go further with this - I can comeback with my ideas. And it is only possible to manage the temperature this way - the humidity cant be used for a 1-10 control signal as it is now

Sincerely Lasse

Thanks Lasse. Let me get back to you on this after I've understood what you just said! ;Bookworm

MnFish1 · Apr 23, 2021

Laith said:
That's a good question.

Here's the issue. The exhaust fan can only be controlled by either the air temp sensor or the humidity sensor (in theory any of the sensors but only one, not multiple ones).

Higher air temp doesn't always equal higher humidity and vice versa. So if I set the 1-10v channel to the air temp sensor it might not turn the fan on because the air temp is not high... but the humidity might be at 65 or 70. And the humidity can be 50 or 55 and the the air temp can be 31 or 32.

I hope that by keeping the fan running at low speed all the time this would solve this issue.

The way I look at it - and I hope this is helping. It does not make sense to try to run one piece of equipment with 2 probes. Here is one example - Lets say the humidity is high - and the fan turns on. Over time this will lower the temperature. I assume that if the temperature is low, you will try to program the fan to go off. Now there are potentially 2 different inputs going into the same controller and piece of equipment. Note - this was just an example - I can picture many permutations of this. IMHO - temperature is the most important - and as Temp goes up - humidity should also go up (i.e. more evaporation). Thus - it seems like its only necessary to use the probe for temperature. IMHO - humidity is not as important (unless there is a special reason on your tan). Again - I see what you're trying to do - I'm just not sure you need to do it...

Laith · Apr 23, 2021

MnFish1 said:
The way I look at it - and I hope this is helping. It does not make sense to try to run one piece of equipment with 2 probes. Here is one example - Lets say the humidity is high - and the fan turns on. Over time this will lower the temperature. I assume that if the temperature is low, you will try to program the fan to go off. Now there are potentially 2 different inputs going into the same controller and piece of equipment. Note - this was just an example - I can picture many permutations of this. IMHO - temperature is the most important - and as Temp goes up - humidity should also go up (i.e. more evaporation). Thus - it seems like its only necessary to use the probe for temperature. IMHO - humidity is not as important (unless there is a special reason on your tan). Again - I see what you're trying to do - I'm just not sure you need to do it...

I get your point about whether I need to do it the way I'd like. I'm also mulling that over!

But evaporation increases with higher water temperatures, not higher air temperatures (I'm pretty sure). I've seen in my tank that when the air temp goes down (in the middle of the dark period for example) to around 27C, the humidity over the DT goes up to around 60-70.

However, during the light cycle the air temps inch up towards 32-33C, the humidity goes down to around 45-50...

And I'm not trying to use both sensors to control the exhaust fan, I've been concentrating on using the air temperature. But then again, during the dark period the humidity is going up because the air temperature is not running the exhaust fan high enough. Frustrating!

It could also be that during the light period, as the fan is running faster due to higher air temps, that is bringing the humidity down...

Laith · Apr 23, 2021

And just to clarify that the GHL air temp/humidity sensor is one sensor with one connection to the P4... It is not two separate connections.

Lasse · Apr 23, 2021

Laith said:
That's a good question.

Here's the issue. The exhaust fan can only be controlled by either the air temp sensor or the humidity sensor (in theory any of the sensors but only one, not multiple ones).

Higher air temp doesn't always equal higher humidity and vice versa. So if I set the 1-10v channel to the air temp sensor it might not turn the fan on because the air temp is not high... but the humidity might be at 65 or 70. And the humidity can be 50 or 55 and the the air temp can be 31 or 32.

I hope that by keeping the fan running at low speed all the time this would solve this issue.

That´s much easier to solve. If you have a 12 V fan - you get a propeller control and 2 pcs 12 V PSU. connect 1 PSU to the propeller control and to a switch outlet - let us say S1. Connect the other PSU to another switch outlet S2. See my figure below

If the humidity is above your nominal value PSU2 will give 12 V to the FAN - it will run at 100 %. PSU1 will give 0 V because the PL command. When humidity is below your nominal value - PSU2 will have o V and PSU1 will have 12 V. The 1-10 V signal from L1 will then determine the voltage to the fan and your airtemp will adjust the fan according to the difference between the nominal air temp and the actual. If humidity will rise again over the nominal value - PSU1 shout down and PSU2 will give 12 V again - 100 %

Below you can see my configuration of my airtemp controller. Nominal in blue and difference between 0 - 100 % in red

Hope this give you some ideas. You will not have a steady run but if the humidity rise to much - you will handle that

NOTE I have not test this - if you use the ideas - do not blame me if its not working

Sincerely Lasse

MnFish1 · Apr 23, 2021

Laith said:
I get your point about whether I need to do it the way I'd like. I'm also mulling that over!

But evaporation increases with higher water temperatures, not higher air temperatures (I'm pretty sure). I've seen in my tank that when the air temp goes down (in the middle of the dark period for example) to around 27C, the humidity over the DT goes up to around 60-70.

However, during the light cycle the air temps inch up towards 32-33C, the humidity goes down to around 45-50...

And I'm not trying to use both sensors to control the exhaust fan, I've been concentrating on using the air temperature. But then again, during the dark period the humidity is going up because the air temperature is not running the exhaust fan high enough. Frustrating!

It could also be that during the light period, as the fan is running faster due to higher air temps, that is bringing the humidity down...

OH - I misunderstood I was under the impression you were measuring water temp and humidity above the tank - sorry that wasn't clear. I thought most people used the fans to help control 'water temperature'. I.e. if the water temp is too high - the fan turns on - to improve evaporation. which then lowers the water temp some.

Again - Its unclear why you're concerned about humidity. Also again - im not trying to argue or criticise either. But - just FYI - at least the way I read this. You are fighting 2 things against each other. If the air temp decreases relative to the tank (with the fan on) - humidity will increase. Just seems like either way - if you can figure out a way to do what you wanted in your OP - that if you use air temp, and it goes up - the fan will increase. When the fan increases - the humidity will increase - and thus the fan will be on. I.e. The fan is going to be on nearly all the time. ???

Laith · Apr 23, 2021

MnFish1 said:
OH - I misunderstood I was under the impression you were measuring water temp and humidity above the tank - sorry that wasn't clear. I thought most people used the fans to help control 'water temperature'. I.e. if the water temp is too high - the fan turns on - to improve evaporation. which then lowers the water temp some.

Again - Its unclear why you're concerned about humidity. Also again - im not trying to argue or criticise either. But - just FYI - at least the way I read this. You are fighting 2 things against each other. If the air temp decreases relative to the tank (with the fan on) - humidity will increase. Just seems like either way - if you can figure out a way to do what you wanted in your OP - that if you use air temp, and it goes up - the fan will increase. When the fan increases - the humidity will increase - and thus the fan will be on. I.e. The fan is going to be on nearly all the time. ???

My mistake, I don't think I was clear on the "fan" I was talking about. I have GHL ventilator fans on the tank that blow air over the water surface but their role is to lower water temperature (not air temperature) through forced evaporation. And they are controlled by the P4 via the water temperature sensor. If the water temperature goes over the nominal value then these "water cooling fans" come on.

The "exhaust fan" that I'm controlling through the air temperature sensor is an in wall exhaust fan that sucks air out from above the tank to outdoors.

Laith · Apr 23, 2021

Lasse said:
That´s much easier to solve. If you have a 12 V fan - you get a propeller control and 2 pcs 12 V PSU. connect 1 PSU to the propeller control and to a switch outlet - let us say S1. Connect the other PSU to another switch outlet S2. See my figure below

If the humidity is above your nominal value PSU2 will give 12 V to the FAN - it will run at 100 %. PSU1 will give 0 V because the PL command. When humidity is below your nominal value - PSU2 will have o V and PSU1 will have 12 V. The 1-10 V signal from L1 will then determine the voltage to the fan and your airtemp will adjust the fan according to the difference between the nominal air temp and the actual. If humidity will rise again over the nominal value - PSU1 shout down and PSU2 will give 12 V again - 100 %

Below you can see my configuration of my airtemp controller. Nominal in blue and difference between 0 - 100 % in red

Hope this give you some ideas. You will not have a steady run but if the humidity rise to much - you will handle that

NOTE I have not test this - if you use the ideas - do not blame me if its not working

Sincerely Lasse

Just a quick question before I study/understand what you have described as a solution: Your screen shot is showing a Dynamic nominal value as not active. Mine shows as active. What does that actually do when it is active or inactive?

MnFish1 · Apr 23, 2021

Laith said:
My mistake, I don't think I was clear on the "fan" I was talking about. I have GHL ventilator fans on the tank that blow air over the water surface but their role is to lower water temperature (not air temperature) through forced evaporation. And they are controlled by the P4 via the water temperature sensor. If the water temperature goes over the nominal value then these "water cooling fans" come on.

The "exhaust fan" that I'm controlling through the air temperature sensor is an in wall exhaust fan that sucks air out from above the tank to outdoors.

Thansk for clarifying - I'm sure if there is a solution - you will get it here. IMHO, its not an issue - but I hope you do get a better answer than that LOL

Lasse · Apr 24, 2021

Dynamic nominal values do not function yet in P4 (but in P3) Off some reason it looks like active is the default in P4. I always put then inactive of safety reasons. However - never notice any thing with this parameter and P4. It is a strong tool when it is in function and I think they will try to make it work against a text file but for the moment it does not work in P4

Sincerely Lasse

Laith · Apr 24, 2021

ok, I've turned off the dymanic setting in all my sensors just to be sure...

Laith · Apr 24, 2021

So, back to the question MnFish1 asked: do I need to do this in the first place? Or more to the point, are my humidity/temp levels something that needs to be fixed?

Here is a graph of air temp, water temp and humidity over the past three days. Keep in mind that my nominal value for water temp is 26.5C. So air temp is peaking at 32.5C, humidity at 71.9 and water temp at 27.1C. I'm not too worried about the water temp, especially as the weather gets warmer the aircon in the room will kick in (my chiller! ;Joyful).

I guess my main concern is more the humidity at 70+ above the tank. Should I be concerned or not? Opinions?

Laith · Apr 24, 2021

Lasse said:
That´s much easier to solve. If you have a 12 V fan - you get a propeller control and 2 pcs 12 V PSU. connect 1 PSU to the propeller control and to a switch outlet - let us say S1. Connect the other PSU to another switch outlet S2. See my figure below

If the humidity is above your nominal value PSU2 will give 12 V to the FAN - it will run at 100 %. PSU1 will give 0 V because the PL command. When humidity is below your nominal value - PSU2 will have o V and PSU1 will have 12 V. The 1-10 V signal from L1 will then determine the voltage to the fan and your airtemp will adjust the fan according to the difference between the nominal air temp and the actual. If humidity will rise again over the nominal value - PSU1 shout down and PSU2 will give 12 V again - 100 %

Below you can see my configuration of my airtemp controller. Nominal in blue and difference between 0 - 100 % in red

Hope this give you some ideas. You will not have a steady run but if the humidity rise to much - you will handle that

NOTE I have not test this - if you use the ideas - do not blame me if its not working

Sincerely Lasse

Many thanks for this Lasse. If I do decide to implement a solution like this I will need to come back to you with questions!

For info, my air temp nominal value is set at 28C, hysteresis at 0.2C and max 1-10 at 5C.

The reason I have the max 1-10 at 5C: my exhaust fan is whisper quiet up until about 70-80% speed. Above that, and especially at 100%, it sounds like a jet engine

. The unit does move *alot* of air though so even at speeds below 70% it's doing its job. My airtemp numbers might be lower if I let it run at 100% (which it would quickly do if I had the max 1-10 set to 1C as you have) but...

MnFish1 · Apr 24, 2021

In my opinion people focus on the water temperature - and not the humidity or the air temperature above the tank. Do you have a closed canopy, etc - that makes you worried about the values? If it were me - I would just keep the water temp where you want - and use the fan to create circulation above the tank - which will improve oxygenation, lower the temp - and the humidity all at the same time. For example - I can see a disadvantage of too high an air temp - and too high a humidity. Aside from electricity cost, I do not see a downside to lowering them (the lowest they will get is to room levels anyway?

Laith · Apr 24, 2021

This is the tank design with the cabinetry around it (the width front to back was reduced to 70cm in the final build).

So it does have a sort of closed canopy on top with panels that are magnetically attached. The reason for the air temp above the tank going up are the Mitras LX 7206 (five of them) that I'm using for lighting. Fantastic lights but the only drawback is they generate heat...