thefunkybuddha Posted December 13, 2019 Report Share Posted December 13, 2019 I am not an expert in ladder logic. I am modifying some code and I need to code an override of a relay that is on O0 of the Jazz outputs. Im landing a 24VDC signal to I0. When the signal is high, I want the Relay to energize. As soon as the signal is low, i want it to de-energize. I have done this in V350 and Samba, but i cant get it to work on the Jazz. The closest I can get is with the reset and set coils. But that latches it. And it is two high signals that will turn it on then off. For some reason, when I replace the same logic with direct coils, i get no response. Please help! Quote Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted December 13, 2019 MVP 2023 Report Share Posted December 13, 2019 If this isn't working for you (see attached), then post your code. Quote Link to comment Share on other sites More sharing options...
thefunkybuddha Posted December 13, 2019 Author Report Share Posted December 13, 2019 I downloaded this to the controller....ONLY that just to see if I could get the I/O to work...I get no response when I apply 24VDC to I0 (#15). Just in case I was mistaking about the physical address I applied the signal to all the Inputs...no response. If I jumer 24VDC O0 my relay energizes. Im overlooking something simple...please help. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted December 13, 2019 MVP 2023 Report Share Posted December 13, 2019 Did you go online with the PLC and see that I 0 and O 0 were energized when the input signal is on? Quote Link to comment Share on other sites More sharing options...
thefunkybuddha Posted December 13, 2019 Author Report Share Posted December 13, 2019 Yes. It is not. Quote Link to comment Share on other sites More sharing options...
thefunkybuddha Posted December 13, 2019 Author Report Share Posted December 13, 2019 If I change the code to this...it works...but it latches. I need momentary, only while the signal is high. Quote Link to comment Share on other sites More sharing options...
MVP 2023 kratmel Posted December 14, 2019 MVP 2023 Report Share Posted December 14, 2019 Is it n/p input on jazz setup corectly? Please see in installation manual. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted December 14, 2019 MVP 2023 Report Share Posted December 14, 2019 If you don't see I 0 on when you go online with the PLC then you have a wiring problem with your input. If a Set coil latches, then it means the input flickered on so rapidly that you couldn't see it. Quote Link to comment Share on other sites More sharing options...
thefunkybuddha Posted December 16, 2019 Author Report Share Posted December 16, 2019 I have my power to the controller and the only thing I have actually wired to the controller are the outputs to terminals O-0, O-1, O-2, & O-3. The inputs, until I figure, I have left disconnected. For the 24VDC signal I am just taking a 20 gauge wire and jumping V+ on the controller to the input I assigned. For example, with the ladder I posted above downloaded to my controller, I will run the wire from the number 1 position of the input terminal block, to the 15 position on the terminal block. If I simply change the coil to a set coil, it works to set the relay. But, as I stated above, as when I remove the 24V signal I need the relay to go off. With a set coil it stays energized. If I had my wiring wrong, I would expect it to not work with the set coil. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Joe Tauser Posted December 16, 2019 MVP 2023 Report Share Posted December 16, 2019 On 12/14/2019 at 12:17 PM, Flex727 said: If you don't see I 0 on when you go online with the PLC then you have a wiring problem with your input. Connect a jumper between 0V on the power and the n/p terminal (5). The n/p terminal sets the voltage reference for the inputs as either sinking (0V = ON) or sourcing (+24V = ON). Since you are using a jumper from V+ to the input, this is considered sourcing. Let us know if this works. Joe T. Quote Link to comment Share on other sites More sharing options...
thefunkybuddha Posted December 16, 2019 Author Report Share Posted December 16, 2019 2 hours ago, Joe Tauser said: Connect a jumper between 0V on the power and the n/p terminal (5). The n/p terminal sets the voltage reference for the inputs as either sinking (0V = ON) or sourcing (+24V = ON). Since you are using a jumper from V+ to the input, this is considered sourcing. Let us know if this works. Joe T. That did it. Thank you all for your help. I am a ChemE by education so I have some fundamental gaps I need to fill. Quote Link to comment Share on other sites More sharing options...
MVP 2023 Joe Tauser Posted December 16, 2019 MVP 2023 Report Share Posted December 16, 2019 Cool. This is what @kratmel brought up but my experience has been that it is not uncommon for an "electricity is not my first love" type of person gets thrust into PLC Land and schematics can be difficult to interpret by those who don't do it every day. Sometimes people just need their hand held. Joe T. Quote Link to comment Share on other sites More sharing options...
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