Chromatography Forum

"Frankenstein" HPLC Arduino controlled. It's a possible reality?

Hey guys, good for everyone.
As mentioned in the subject, I would like to build a chromatography system with old modules, parts and all the other material available to me at the university.
Ace in the hole of this system is the ability to use the arduino to "conduct the orchestra".

I'm already searching for material and have found things like pump control https://www.youtube.com/watch?v=K2FaXSFcAzQ

Could any of you give your opinion?
ppreciate.

Interesting project! Also very close to what I'm currently doing.

I have in the past had success controlling a home-built GC detector with an arduino as ADC, so on the detector side of things you won't have much problem. All older and some newer HPLC detectors has a standard 0-1V or 0-10 mv output to feed to an external ADC/chart recorder, which helps a lot.

Pump control is a bigger hurdle. I think the old Waters pumps, like the one in the video has a fairly simple PWM interface. you can clearly hear the audible modulation when it's sped up/slowed down.

The other option is to make an GPIB shield for the arduino and then try to interface it with the firmware of intelligent pumps or detectors. This i think is much harder.

Good luck!

--Christoffer

Why "Frankenstein"?

Agilent modules sit on CAN bus
Knauer modules sit on KNET bus (rs-232 based)
Gilson sits on GSIOC (rs-232)
Hitachi maps all on usb

Who cares if you equip each module with arduino and connect them with bus whatever you like - I2C, Ethernet, RS232.

AFAIK there is pump modules (piston+wheel) with step-motor. It is one of arduino profession - controlling the step motors.

BUT built-in ADC is far from analytical grade. Consider external 22-24bit Sigma-Delta with proper shielding and grounding and clean power supply connected to Arduino.

Why "Frankenstein"?

Agilent modules sit on CAN bus
Knauer modules sit on KNET bus (rs-232 based)
Gilson sits on GSIOC (rs-232)
Hitachi maps all on usb

Who cares if you equip each module with arduino and connect them with bus whatever you like - I2C, Ethernet, RS232.

AFAIK there is pump modules (piston+wheel) with step-motor. It is one of arduino profession - controlling the step motors.

BUT built-in ADC is far from analytical grade. Consider external 22-24bit Sigma-Delta with proper shielding and grounding and clean power supply connected to Arduino.

Thank you for the tips.
That's exactly what I think about, connecting diverse systems using the tools that arduino gives us.
As an enthusiast, I understood what you meant by the techie, but I have no idea how to do it. lol

Why "Frankenstein"?

BUT built-in ADC is far from analytical grade. Consider external 22-24bit Sigma-Delta with proper shielding and grounding and clean power supply connected to Arduino.

Do you have any idea of another tool that can give higher quality to the transfer of this data?

Interesting project! Also very close to what I'm currently doing.

I have in the past had success controlling a home-built GC detector with an arduino as ADC, so on the detector side of things you won't have much problem. All older and some newer HPLC detectors has a standard 0-1V or 0-10 mv output to feed to an external ADC/chart recorder, which helps a lot.

Pump control is a bigger hurdle. I think the old Waters pumps, like the one in the video has a fairly simple PWM interface. you can clearly hear the audible modulation when it's sped up/slowed down.

The other option is to make an GPIB shield for the arduino and then try to interface it with the firmware of intelligent pumps or detectors. This i think is much harder.

Good luck!

--Christoffer

Thanks so much for the tips.
I had thought of things like that too, but as I said to the Antonk, I need to study a little more the practice of it all.

Why "Frankenstein"?

Agilent modules sit on CAN bus
Knauer modules sit on KNET bus (rs-232 based)
Gilson sits on GSIOC (rs-232)
Hitachi maps all on usb

Who cares if you equip each module with arduino and connect them with bus whatever you like - I2C, Ethernet, RS232.

AFAIK there is pump modules (piston+wheel) with step-motor. It is one of arduino profession - controlling the step motors.

BUT built-in ADC is far from analytical grade. Consider external 22-24bit Sigma-Delta with proper shielding and grounding and clean power supply connected to Arduino.

Knowing the electrical protocol for data to/from an instrument doesn't help much unless you also know what all commands back and forth are, how handshaking is implemented and how bulk data is transmitted. This information is usually proprietary. Correct me if i'm wrong, but i would think this exercise is also meant to free up a HPLC system from some specific vendor's proprietary softare/interface cards etc.

Why "Frankenstein"?

BUT built-in ADC is far from analytical grade. Consider external 22-24bit Sigma-Delta with proper shielding and grounding and clean power supply connected to Arduino.

Do you have any idea of another tool that can give higher quality to the transfer of this data?

https://www.analog.com/media/en/technic ... AD7710.pdf

You need SCLK, SDATA, DRDY, A0 - 4 lines to drive this chip.
It is read bit-by-bit from MSB to LSB. Examples are in Datasheet and Application notes.
There are even simpler chips of AD which can be driven by 3 pins. Use parametric search.

Knowing the electrical protocol for data to/from an instrument doesn't help much unless you also know what all commands back and forth are, how handshaking is implemented and how bulk data is transmitted. This information is usually proprietary. Correct me if i'm wrong, but i would think this exercise is also meant to free up a HPLC system from some specific vendor's proprietary softare/interface cards etc.

Brave person tries to built is-own HPLC system.
There is no need to reverse these protocols (although this is not so hard).
I meant the approach is the same in all HPLC systems and the Arduino is PROPER tool to do the task.

About the pumps:
http://www.akvilon.su/products/analitic ... tayer/688/

This russian company sells its own HPLC pump built of:
* Schroff housing
* US-made piston pump module driven by step motor
* Microchip PIC controller which drives the step motor and performs commands of LAB-Alliance protocol.
RU - run, ST - stop, FL 1.5 - flow of 1.5 cc/min ......

I've seen this pump inside, ether as Knauer P61L.
Almost empty box with step-motor driven pump + microcontroller of your choice.

And, YES - Arduino can be used as protocol translator.

Once I even seen microcontroller-based module in GC world which translate HP7673 automatic liquid sampler commands into the language of Shimadzu AOC sampler. I.e. the GC 5890 believe it is working authentic 7673 but it was Shimadzu.

P.S. Once you need HPLC sofware - please consider:
http://www.unichrom.com/unichrome.shtml
Custom driver development:
http://www.unichrom.com/chrom/ucddke.shtml

Once you get machine working - I think we can supply personal license for free