Jebao Dosing Pump Calibration (DP4)

[potatocouch]

For those that use Jebao Dosing Pump, I have quick questions.

So I have calibrated all 4 pumps with 100ml calibration and is currently trialing all 4 pumps with RODI water.

These past 2 days, I have noticed that the dose excreted by these pumps seems to be slightly over.

For example: pump #1 programmed to dose 2 ml over 5 dose ... I should be getting 10 ml in total but after measurement, I'm getting close to 15 ml.

Pump #3 was just programmed to dose 6 ml over 5 dose ... I have the opportunity to measure the 1st drop but it dose close to 8 ml.

The question: from your experience, is it better/easier to calibrate it again using the 100 ml but stop at approx. 80 - 90 ml? My logical thinking is perhaps it will dose slightly lower or is it better/easier to just reduce the dosing ml in the program?

 

[JaimeAdams]

I would try to re-calibrate it to the 100 mark. It is likely that there may have been air bubbles in the line or pump. It is suggested to run the pump for awhile and then re-calibrate it.

 

[potatocouch]

I would try to re-calibrate it to the 100 mark. It is likely that there may have been air bubbles in the line or pump. It is suggested to run the pump for awhile and then re-calibrate it.

@JaimeAdams aaah I forgot to mention .. yes I did that for all 4 before calibrating them.

At the start of calibration , since no more air bubbles, water straight out so I think the calibration process is okay but weird that it dose more than it should.

 

[JaimeAdams]

@JaimeAdams aaah I forgot to mention .. yes I did that for all 4 before calibrating them.

At the start of calibration , since no more air bubbles, water straight out so I think the calibration process is okay but weird that it dose more than it should.

I literally set one of these up for a friend 3 hours ago.

I would do the re-calibration and then see if it is still off.

If it still over doses I would simply adjust the amount to be dosed. Add input for 4 ml to get 6 etc.

 

[Terry4505]

I run three of these pumps. I don't stress over the exact dose, and just test often and adjust. I test my Alk daily, so it doesn't matter was the actual does is to the ml, I just adjust the dosing up or down as needed.

The tank has been running for year with no problems, mostly SPS.

 

[Psiber_Syn]

Also did you pull the dosing tubing around to get out the kinks? Mine was crimped pretty tight on one of the heads and was almost double the amount of doses to get the 100ml just a suggestion

My dp4 does great no issues at all ime

 

[potatocouch]

Folks @Terry4505 @Psiber_Syn @JaimeAdams

I think I'm overthinking this but I thought I ask the questions :)

TWO questions:

1. They (Jebao) said in the manual to calibrate with RODI water ...
   Alk/Ca/Mg solution is somewhat thicker than RODI water ... By thick, I meant it's not as liquid as RODI water ...
   Wouldn't the calibration be off then, as we are calibrating using RODI water but when doing real dosing, we use these "thicker" solutions?
   
   
2. Will there be any issue with Alkalinity solution causing problem with the peristaltic pump?
   The reason I asked is because I've dosed Alk in the past, using syringe ... and and I have not been using that syringe for quite some time not (approx. 3 months or so) ...
   The syringe is now very tough to operate as I believe the solution may have precipitate inside the syringe.
   

Anyone else that can chime in, will be much appreciated :)

 

[reeferfoxx]

TWO questions:

1. They (Jebao) said in the manual to calibrate with RODI water ...
   Alk/Ca/Mg solution is somewhat thicker than RODI water ... By thick, I meant it's not as liquid as RODI water ...
   Wouldn't the calibration be off then, as we are calibrating using RODI water but when doing real dosing, we use these "thicker" solutions?
   
   
2. Will there be any issue with Alkalinity solution causing problem with the peristaltic pump?
   The reason I asked is because I've dosed Alk in the past, using syringe ... and and I have not been using that syringe for quite some time not (approx. 3 months or so) ...
   The syringe is now very tough to operate as I believe the solution may have precipitate inside the syringe.

Anyone else that can chime in, will be much appreciated :)

Answer to number 1. You're overthinking.
Answer to number 2. You can and will purchase new tubing in the future. Even pump using ro/di will need tube replacement, eventually.

 

[jsker]

Just finished re-calibrating my 2 Jebao and making sure my line are not restricted. I am also replacing all my tube with surgical tubing. I have had my Jebao's running for 11 months and figured I would check the dosage and change the line. I do have a little brittleness with the alk line at the end as it enters the sump. The rest of the line are fine.

 

[potatocouch]

Thank you @reeferfoxx :)

Thank you @jsker :)

 

[jsker]

Thank you @reeferfoxx :)

Thank you @jsker :)

You are welcome, I like the avatar:)

 

[potatocouch]

OK .. i was thinking about this ..... I need to pick your BRIGHT brain on this on how should I do this easier (easily).

So they say I need to do the trial of this dosing pump on the exact position where you would have in, when it's going LIVE.

• At this stage, I'm doing all 4 channels output to plastic containers outside the tank/sump.
• I've been trialing the above method for approximately 3 days now and so far am happy with the consistency but the real test comes when the outlets are hooked to the tubes holder into the sump.
• Hooking up the tubes holder into the sump is easy; putting the tubes to the tubes holder is easy.
• My approach is not letting the dose to go into my system; my preference is to capture each tubes output into separate container (in the sump) just for a day.
• Once completed (for the day), I then take out the containers and measure each of em and see if I'm happy with it.

I was thinking to just strap 4 x small cup (container) ... just like those dosing cup from Red Sea inside the sump, ensuring each tube goes into their respective cup.

Do you have better (more efficient) idea than that?

 

[morpheas]

These pumps are not meant to dose minute amounts (1-5 ccs) accurately. They're not built for that. They can dose but they'll be approximate. You're calibrating it at 100cc and trying to dose 2 (that's 2% of the full scale). You need to lower your expectations of it :) i had the same predicament, needing to dose small amounts in which case i made dilutions. I diluted my alk and cal 5 times and instead of dosing 2cc i dose 10 which is much more achievable.

If you think about it, if you ask it to dose 2cc and it's a drop more it could be as much as 0.5cc (which is certainly a possibility due to the small amount) which is 25% error. When you dose a more reasonable amount, say 10, 0.5 cc is 5% which is much more acceptable.

If you want the kind of precision you're talking about you have to go with either a more accurate pump (like the DOS which it's design allows it to be much more accurate) or my personal preference, at the encouragement of @twilliard, a medical grade infusion pump (nothing more accurate!).

So to summarize, i think you are off spec for this pump and in order to fix that you have to either adjust the dosing amount (dilution would me my choice) or change direction on the hardware ( FWIW i actually did both).

 

[potatocouch]

@morpheas I understand if the error rate stays at 0.5 ml when dosing 10.

But when you dose more, the overdose tend to be more too, so margin of error may be the same.

I'll give it a shot though.

 

[morpheas]

I feel your pain and predicament. I faced the same challenge during my experience with the DP4. I am not sure if the BM or other equivalents of the DP4 are better (maybe someone will chime in on that) but my own feel is that it is simply not constructed in a way to give it high accuracy, especially on the low range. The only way I found easy to battle that was, as I mentioned, to dilute. I know it's not the answer you're looking for but I hope it can help guide you in a direction that will solve your problem.

 

[Gary Inwood]

@JaimeAdams aaah I forgot to mention .. yes I did that for all 4 before calibrating them.

At the start of calibration , since no more air bubbles, water straight out so I think the calibration process is okay but weird that it dose more than it should.

Are you using the same length of tubing? because you change the length of the tubing that would screw the calibrating etc to hell.

 

[Gary Inwood]

These pumps are not meant to dose minute amounts (1-5 ccs) accurately. They're not built for that. They can dose but they'll be approximate. You're calibrating it at 100cc and trying to dose 2 (that's 2% of the full scale). You need to lower your expectations of it :) i had the same predicament, needing to dose small amounts in which case i made dilutions. I diluted my alk and cal 5 times and instead of dosing 2cc i dose 10 which is much more achievable.

If you think about it, if you ask it to dose 2cc and it's a drop more it could be as much as 0.5cc (which is certainly a possibility due to the small amount) which is 25% error. When you dose a more reasonable amount, say 10, 0.5 cc is 5% which is much more acceptable.

If you want the kind of precision you're talking about you have to go with either a more accurate pump (like the DOS which it's design allows it to be much more accurate) or my personal preference, at the encouragement of @twilliard, a medical grade infusion pump (nothing more accurate!).

So to summarize, i think you are off spec for this pump and in order to fix that you have to either adjust the dosing amount (dilution would me my choice) or change direction on the hardware ( FWIW i actually did both).

You can not dose cc's with jeboa DP-4 it doses in ml and my jeboa dose works perfectly

 

[reeferfoxx]

Are you using the same length of tubing? because you change the length of the tubing that would screw the calibrating etc to hell.

Calibration is based on the speed of the motor. Once you fill the tube with fluid and begin the dosing schedule, there shouldn't be a difference.

 

[doughboy]

These pumps are not meant to dose minute amounts (1-5 ccs) accurately. They're not built for that. They can dose but they'll be approximate. You're calibrating it at 100cc and trying to dose 2 (that's 2% of the full scale). You need to lower your expectations of it :) i had the same predicament, needing to dose small amounts in which case i made dilutions. I diluted my alk and cal 5 times and instead of dosing 2cc i dose 10 which is much more achievable.

If you think about it, if you ask it to dose 2cc and it's a drop more it could be as much as 0.5cc (which is certainly a possibility due to the small amount) which is 25% error. When you dose a more reasonable amount, say 10, 0.5 cc is 5% which is much more acceptable.

If you want the kind of precision you're talking about you have to go with either a more accurate pump (like the DOS which it's design allows it to be much more accurate) or my personal preference, at the encouragement of @twilliard, a medical grade infusion pump (nothing more accurate!).

So to summarize, i think you are off spec for this pump and in order to fix that you have to either adjust the dosing amount (dilution would me my choice) or change direction on the hardware ( FWIW i actually did both).

^^this.
pump is calibrated for 100ml, and you do 2ml/5 or 0.4 ml per dose. That's not going to work. It is a usage issue, not a product issue.
fwiw, these pumps can be made to do small dose accurately if you diy the hardware and software.
this is an old post from my diy thread where I calibrate to 2ml, exactly.

http://www.reefcentral.com/forums/showpost.php?p=23004725&postcount=804

2ml is the amount I dose so I calibrate to that volume. If you calibrate to 0.4ml, then it will dose 0.4ml accurately.