Can the KHD auto dose to the .1 (tenth or 1/10th)

[AZMSGT]

I watched a video on setting up the KHD to set up autodosing. But it really only covered a single digit adjustment. Like 8.0, 9.0 or 10.0.. it didn’t go into the ability to make finer adjustments down to the 1/10th of a point. Is it able to make those finer adjustments for accuracy and stability?


This is the video I watched.

 

[griff500]

I believe you simply enter what you want, such as 7.6, and it aims for that.

It keeps the level quite tight to the number you set - usually within 0.1 or so.

 

[Sisterlimonpot]

Ken, what are you dosing that requires such precision? I was surprised that the Versa can dose as low as 0.015ml over the course of 60 minutes. Look at the dose per minute... it's 0.5μL/min... WOW!!! you definitely need a pipette tip on the end of the tube for that type of dosing.

 

[AZMSGT]

Actually my Alk I’m manually dosing 15ml per day to stay at 8.4kHD ideally I want to stay pegged at 8.4 or close to it.

 

[griff500]

The KHD is certainly capable of doing that.

 

[AZMSGT]

The KHD is certainly capable of doing that.

Can you elaborate beyond what the video says regarding the subject? Thanks

 

[griff500]

I hadn't looked at the video when I replied - I was speaking from my experience of the KHD. I'm not quite sure how to elaborate on the statement that it will do what you are looking for - that's pretty much what it is designed to do and it works very well.

 

[AZMSGT]

I hadn't looked at the video when I replied - I was speaking from my experience of the KHD. I'm not quite sure how to elaborate on the statement that it will do what you are looking for - that's pretty much what it is designed to do and it works very well.

How about screen shots of your set up?

 

[griff500]

Screen shots? What did you want to see?

 

[AZMSGT]

Screen shots? What did you want to see?

How about the KHD control screen and the dosing pump screen tied to that control. Please

 

[griff500]

These?

 

[AZMSGT]

These?

Looking at your set up on the control screen it shows that your set for a nominal value of 8 with a variable of 1 dkh. That is the part I want to break down to the .1 instead of 1 full point.

 

[griff500]

The second paragraph in the control section states that this is automatically calculated. I think I mentioned earlier that it controls within 0.1 to 0.2 of the target value in my experience and you can set the target value to 8.2 or whatever you want.

The text you are focussed on is simply saying what happens if a large deviation occurs - maximum adjustment of dose based on your volume change setting. It is not saying that it only adjusts when a deviation of 1 happens... I think you might be misunderstanding this.

 

[MabuyaQ]

Looking at your set up on the control screen it shows that your set for a nominal value of 8 with a variable of 1 dkh. That is the part I want to break down to the .1 instead of 1 full point.

That is not how it works. When a 1dKH is measured from nominal a dosage change is made equal to the set volume change (in above screenprints 50%). With any change smaller or larger it will calculate the required % volume change.
The KHD is different from other GHL type measurements where you set nominal value and hysteresis. Here you set nominal value and the KHD will calculate the required adjustments to keep hysteresis as small as possible. The more measurements the better this works and you can keep your KH from changing more than 0.1 dKH at any set nominal value.