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...
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...
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...
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...
We are putting 30Kppm+ brine through an electrolysis cell and are losing the platinum off of the Pt plated Ti electrodes rapidly on the anolyte side. We experimented with a graphite electrode and ran into some design problems with the porosity and erosion due to the tar/pitch that holds the...
Have 2Vac riding on a 6Vdc 0-10V analog input line driving the program bonkers. I suspect a dying rectifyer. I already have series resistors in line that scale the signal to the 0-10V range. The rectifier has a smoothing cap with bleed resistor. Grounds are all at a single point on the chasis...
