Yes danw2. 100-reg-reads worked fine for about 3 months. Yesterday I stepped the register count up one by one and found that 80 is the exact cutoff. 81 is a no-go but 80 comes back fine consitently. I was hoping to have written the DAQ module in a way that it would be compatible with any future...
Hi Gents, Question for ya...
We have a new design, PLC driven machine that loads its recipe at the beginning of each shift via Modbus write of 95 register values. On top of that periodic routine we wrote a vba-over-MSAccess app for simple DAQ, analysis, and troubleshooting via modbus as well...
Hello,
We have a process involving several streams feeding in at slightly different pressures. We were using Plastomatic flow control valves in different sizes for each stream to achieve the right proportion. These work as a variable orifice reacting to pressure to always permit only the...
Hello,
I have been using a dosmatic fluid driven doser to add 2.5% of additive to a 1 gpm stream. It sufficed for the initial proof stage but now we need to spec something a little more permanent, reliable, and if possible feedback fault detectable by PLC. What methods would anyone recommend to...
Hi all,
Currently using DPDT relays to reverse polarity on electrochemical cells. We are wanting to FET the power to them to be able to PWM the power and periodically reverse polarity. I found some circuits where all N-MOSFETS were used by driving the ones on the high side with a larger gate...
So, the load will vary amongst a few different applications and the PSU needs to be able to support each one. Its an electrochemical thing with varying electrolyte and therefore varying conductivity and ion targeting. thats why the +/-5V
Speaking of cool new technology getting cheaper...
We started using guided wave radar to indicate mechanical positions and fluid levels. Check out IFM efector.
Hope it helps. I'm usually the guy asking the questions.
I have a dirty dc supply consisting of rectified variacs on a common stepper-motor shaft. Currently I have 1kVA isolation transformers in line that have 10amp breakers built in. I'd rather switch out breakers and try to pull closer to the wall rated 15A or if it is available 20A. I have circuit...
Have a membrane seperated electrolysis cell with different volumes of gas generating on each side and influencing flow by tumbling through the lines with the liquid. We implemented a gas separation chamber to bleed it off, compress and bottle the gas but...
The gas volume generation varies and...
I need to balance two flow circuits on the range of 1-10LPM. I was thinking of hooking up two paddle wheel flowmeters to the plc to output to two pwm solenoid valves. So far the 'beans' look like they're going to be adding up to around:
~$300 per flowmeter (X2) =$600
~$150 per sig...
Thanks for the quick reply.
This is turning out to one of those things you kick yourself because you should have known it, and I did, must have had it repressed back in the depths of the abyss.
Have a great day.
Here's the setup:
Multiple variacs ganged on a shaft and controlled by stepper motor. Each variac has its own rectifier and ripple smoothing cap. Ripple is acceptable for app.
Controlling PLC needs to see rectifier output VDC in order to step accordingly. In order to see it I have a signal...
Brine Composition: NaCl or KCl, corrosion has been the same
Electrolysis temp: Inlet brine temp is approx 15C
Current Density: Approx 0.1 Acm^-2
Cell Voltage: Approx 9V
I haven't heard of Pourbaix diagrams but am checking them out.
THX
This is a new setup. We were simulating this voltage feedback with a pot in test. Now that we have switched to pull the voltage feedback off of the rectifier output we are getting the fluctuations.
