vettedrivr

I've had 4 die in the last 2 years. Same problem each time, micrologix locks up with the fault light on solid, can't get communication with it. Rockwell had a batch of them get out with what I think the tech said was a comm port circuit defective which was what was causing it. Contact your local distributor and give them the serial number, if it's in that group of problem controllers they will replace it for free. Never had a power supply problem. You will get faults saying the program is corupted if you are switching inductive loads like solenoid valves without spike protection on the outputs. I have 15 Micrologix 1000 in service, the 4 recalled units are the only ones that have gone bad, the replacement units are working great. All our other problems with them have been self inflicted.

Our eConnect runs us about $900 per year, for that I get 3 calls to RA for help and the latest update of all the software packages (4) we have. My understanding of how they decide what to charge WAS based on how many software packages you had but now it's based on how many processors (you're willing to admit) you have. Since I don't make a lot of calls for help and that they always have the answer to whatever question I may have, it has always been worth the money to my company. Be cautious though, I believe eConnect is only good for phone calls during regular business hours while DirectConnect is good 24/7.

I would suggest using diodes across the isolation relay coils, 1N4001 diodes would be a good place to start.

Just thought I'd add my perspective. Last Thursday I had a question about the proper usage of a piece of test equipment at my plant, called the manufacturer, got run all over to every extention they had, got no one to talk to other than the phone operator, left a message at 2 extensions, no call backs as of Friday afternoon when I left work. Friday I had a problem with a different piece of equipment, called the manufactuer, second extension I was directed to got me a tech person. Although somewhat helpful he informed me that that piece of equipment was obsolete (3 years old) and that there was no trade in for the new equipment, no tech support or parts available or repair service available after next year. Any of their equipment we had after that time was just tough luck on our part if we couldn't get it fixed ourselves. We have the RA eConnect support contract for our PLC software. The few times i've called with a question I never waited more than 3 minutes for a tech support person, they have always diagnosed the problem first time, called me back to follow up, and software updates arrive at regular intervals. I guess with me the bottom line is you get what you pay for because I have found 4 words that never seem to go together: GOOD - FREE - CUSTOMER SERVICE.

Stephane, You are attempting to control and analog system with a digital output, this is never going to give you good regulation. When the output comes on and turns the heating coil comes on at full power, the temperature in your process increases until you reach the setpoint. When the setpoint is reached, the coil turns off and you get over shoot as the coil does not cool off immediately. Then as the process cools and the controller deadband comes into play, you will have to reach a certain temperature under the setpoint before the heating coil comes back on. The process continues to lose heat until the coil can catch back up. If you can replace the solid state relay with and variable voltage transformer that increases or decreases voltage with a small motor and drive the motor with and analog output card you will get much better regulation. The problem... motor driven variable voltage transformers are very expensive.

Thanks, that does answer my question. I would have liked to have gone to the St.Louis trade show but I would have had to take vacation time to do it. You nailed the problem I've been running into, people with press controls to sell and not enough cross technology knowledge to carry them through. I will proceed with the retrofit using as many safety features as possible (Light curtains, gate interlocks, backup pressure control/monitoring, anti-tie down two hand operation, safety relays, and so on). If anyone has anything further to add I would appreciate your input. Thanks.

Thanks for the responses guys. Just to clear up a few points, we have standardized to Allen Bradley PLC's 20 years ago. In the last 9 years my plant has gone from 11 PLC's to 44 PLC's. The SLC 5/05 will be used because of the ethernet capability and the fact we are moving toward data and production number gathering as part of engineering and production management involvement although no initial data will be taken from the press production. We presently have no compact logic or control logic controllers in the plant and unless we find a specific need for them they will be slow in coming. I realize Rockwell Automation makes a packaged press control (Omega) geared more toward mechanical stamping presses and it was then shoved over into hydraulic press control packages just as a way of selling more press control units (I've spoken to their reps on this). In fact, some of their press control configurations call for a THIRD SLC 500 processor to take care of additional logic that might be needed for other options. OSHA 29 CFR 1910.217 addresses mechanical stamping presses and excludes hydraulic presses. ANSI B11 section doesn't say anything new and ANSI is only a suggested guideline anyway. If spoken to press control manufactures who provide control packages with a single processor and those that have packages with a dual processor and I'm getting the run around as far as what I have to have. Everybody gives me an opinion on what is needed based on what they have to sell me. I have retrofitted a lot of machines to PLC control but never a hydraulic press. Now, does anyone know what I ABSOLUTELY HAVE TO HAVE as far as single or dual processors to retrofit my press. Thanks in advance for your input.

I am in the process of retrofitting a 4 post 500 ton hydraulic press with a new control system. I have read the OSHA standard for press controls which states if using a PLC for press control it has to be a redundent processor system. It also goes on to say that hydraulic presses are exempt from such requirements but doesn't say much else on the subject and OSHA requirements read like a mud cake recipe. I am planning on using a SLC 5/05 and panelview 550 as the main control and LDT's as ram and cushion position sensors. Several press control manufacturers have been contacted for the safety requirements and the ones that make dual processor controls (Including Allen Bradley) have told me that dual processors are Recomended but won't come right out and say that 2 processors are not absolutely needed. I will have all the usual safety equipment such as light curtains, anti-tie down two hand controls, gate interlock switches, and probably safety feedback relays. Did I miss anything in my reading or can someone show me what else is ABSOLUTELY REQUIRED. Thanks

I'm having a problem with a machine that has a SLC 5/05 connected to a panelview 300 through an AIC+ module. The problem is the panelview writing date and time information to the SLC 5/05 time and date registers. In the SLC program I read the time and date registers as a data storage function but nothing ing the program writes to these registers. No data in the SLC time/date registers gets over written with the cable to the panelview unplugged. I know the is a timed write function in the panelview to send data to these registers and the time interval can be changed. Does anyone know how to disable this function? Or at least get the panelview to write the correct info to the SLC Registers? Normal tags work fine. When looking at the SLC date and clock registers I see Day Of Week S:53L = Saturday, Date S:39-37 = 24 3 6. When I click on the set time and date button it changes to: Day of Week S:53L = Friday, Date S:39-37 = 24 3 2006. After a minute when the panelview writes to the controller it jumps back to Saturday 24 3 6. I have tried setting the date and time on the panelview and I have tried reloading the panelview application with the year setting on the 4 digit setting. Nothing works. Also it should be known that there are 4 of these machines running the same program and hardware configurations and they all do the same thing. The panelview shows 2006 in the year window of the time and date setup screen but writes a 6 to the SLC register. What am I missing???