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Hi there
I work in a big Company that work With modbus systems. Modbus that Controls lights, heating, VAV/HVAC, Fire Dampers, UPS, repeaters for modbus etc.
we're having trouble finding out which is the trouble and have been trying several type of Methods to Ensure that we have eliminated all ends.
- reverse polarity
- combined ground
- eliminating noise on the bus
Fire dampers go via 240v and the rest go via 24v AC. The problem is that the fire dampers are the problem here and we can't figure out which is the problem. there are several floors that has the same system which we combined the ground for eliminating noise on the bus. but on the last floor we haven't had any Luck so far. The system go via Niagara and we've put a JACE up at each repeater to check how the communication on the bus was after each repeater (there are 2 Modbuses in this floor and each BUS has 3-4 repeaters). One bus is of course better than the other but it isnt good enough for delivery, but for Modbus 1. It's like from every repeater you go to and the further you get to the end of the modbus the better it gets.
But for the other it's more like the opposite. The main problem here is the signal. we are having interference on the buss line so Our Components that run on 230VAC are not able to have a good and stable communication. So we are hoping that you could give us some inputs on what to do here.
I work in a big Company that work With modbus systems. Modbus that Controls lights, heating, VAV/HVAC, Fire Dampers, UPS, repeaters for modbus etc.
we're having trouble finding out which is the trouble and have been trying several type of Methods to Ensure that we have eliminated all ends.
- reverse polarity
- combined ground
- eliminating noise on the bus
Fire dampers go via 240v and the rest go via 24v AC. The problem is that the fire dampers are the problem here and we can't figure out which is the problem. there are several floors that has the same system which we combined the ground for eliminating noise on the bus. but on the last floor we haven't had any Luck so far. The system go via Niagara and we've put a JACE up at each repeater to check how the communication on the bus was after each repeater (there are 2 Modbuses in this floor and each BUS has 3-4 repeaters). One bus is of course better than the other but it isnt good enough for delivery, but for Modbus 1. It's like from every repeater you go to and the further you get to the end of the modbus the better it gets.
But for the other it's more like the opposite. The main problem here is the signal. we are having interference on the buss line so Our Components that run on 230VAC are not able to have a good and stable communication. So we are hoping that you could give us some inputs on what to do here.