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I would like to ask for help with the hookup of a rope switch to a conveyor system. My controls knowledge is a bit rusty.
The rope switch is mounted next to the lower conveyor and has common, normally open, and normally closed terminals. The conveyor system has 2 start/stop button sets to control 2 conveyors, respectively. Actually, it has 4. the original start/stop buttons (2 sets) are in the lower conveyor shack. the company built a tower and extended the controls to the tower (2 start stop button sets in the tower).

As I have it now, the rope switch will prevent the conveyors from starting, but it won't stop it. Is it a simple matter of hooking the normally closed contact of the rope switch in series with power source the first start/stop switch set? Or does more need to be done to shut the motor off? Will opening the circuit kill the poer of the motor starter and cause the conveyors to stop?
Thanks for any advice.
 

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same as an e-stop
 

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same as an e-stop
are you using a safty relay?
Here's what he is leading you to (if I may greenman). The PURPOSE of a rope switch on a conveyor is so that if someone walking along the conveyor somehow trips and falls onto it, he (or she) can reach for the rope ANYWHERE along the length, pull it, and not only will the conveyor stop, but it CANNOT be restarted until someone with authority has investigated and made sure that the danger has passed. It needs to function just like an Emergency Stop push button, it's just that you may not be able to get to an E-Stop when being carried along the conveyor belt.

So if you have it wired as you describe, it is essentially pointless because you say it will NOT stop the conveyor if it is running. That is the entire reson behind having the rope switch. You need to fix that immediately.

The safety relay issue is like this: there are some types of rope pull switches that, if engaged, cannot be mechanically reset without a special key or something like that. This is to ensure that the person with authority, who possesses that key, is solely responsible for making sure everyone is safe before allowing the conveyor to re-start. If you use a rope switch that does NOT have that mechanical feature, then you must do this electrically. In the past, here in North America, we have done that with a simplistic "Master Control Relay" (MCR) for years. But how that is implemented, reset and tested was up to the user to decide. Everywhere else in the world, they require what is called a "Safety Relay" which does essentially the same thing, but has built-in logic protocols regarding the reset, testing and failure modes that enhance the human protection. Most people here in North America are going to that kind of system not only because it is less subjective, but also because our safety rules are destined to align with the rest of the world very shortly anyway, so you might as well get ahead of the game of you are designing something new. All of the major component manufacturers now offer Safety Relays, I strongly suggest that you call for help with that if you have never seen one.
 

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Normally the pull cord or rope is used to stop only. Once it is reset another button should be used to reset the emergency stop relay before anything can start. We also can't have multiple start buttons without a selector switch to determine which paenl controls the start up. We used a MCR for years to do this but recently switched to the safety relays for e-stop circuits. We also drop out the power to the PLC outputs with the e-stop relay. If the start is in a remote location we normally put a delay in the start circuit and sound a horn to alert personnel to the machine being started.
 
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