turn the controller off?

[rasheedy 0]

hi every 1 i'm new it the plc, i would like to ask question................ we have allen bradley controllogix 1756, and also 1756-hsc. which connected to compressor, used to pick up the speed but we got zero reading, the electricians has tested that magntic pick up speed and they said i'ts ok. i'm thinking to cut the power supply for the controller and put it on again and i'm afraid if i'm ganna earse the softwre from controller and may ask to download it again "i can download the to the controller" but i'm not sure if there is other devices may affected and make a big problem......... so should i cut the power or there is another solution for that issue, note: we are using rslogix5000 please advice.. Amr Alrasheedy

[panic mode 246]

not sure what you mean.... do you have this thing running without ever being powered down? is it tied to other systems? do you plan on rebooting PLC (just PLC) or something else too? are you concerned with PLC loosing program or startup trouble due interlocks with other systems?

[rasheedy 0]

yes, it was runnig without powered down. no, it is't connected to other systems it's seperated. yes i want to reboot that plc only. yes, i'm

[panic mode 246]

well the best thing you can do to boost your confidence is to go online, make sure you have current version of program and make fresh backup in case data has been changed. this will also verify if your software version matches controller and you can practice connecting (going online).

[Kiwi Sparky 0]

Have you used a scope on the "encoder" to confirm operation. I know you said the electricians have checked the "magnetic pickup speed" but if it is conected to a HSC the pulses will be very fast. I have been to a lot of call outs to "fix" faulty PLC's/High speed counters only to find the problems are with the encoders or encoder wiring

[rasheedy 0]

guys, we fixed that it was a twisted connector on the Mag Pickup and an alarm on the Ignition module,now these are fixed and compressor working fine thanx alot.