2stepsforward
Member
We’ve been using a Gem80-142 to provide a serial link to a group of starter & drives for finfans and pumps for many years. The GEM80 uses port 1 on its ribbon cable to give serial information to the drives for remote start/ stop and running indication via an rs485 link.
Port 2 of the GEM80 ribbon cable needs to communicate to our DCS system (in this case Honeywell TDC3000) via a Data Hiway Port using the Modbus RTU protocol. The GEM80 uses ESP protocol, and this previously was wired through an rs422-current loop converter and then an ESP-Modbus converter. The ESP-Modbus converter acted as a Modbus Slave to the TDC system and as a master to the GEM80.
We had a big plant upset recently which was finally traced back to a wire shorting across the back off the RS422 to RS485 converter PCB. Prior to this, all Port 2 operation stopped.
The GEM80 has been checked over, tested etc and is fully functioning. Port 1 is functioning fine too. However we believe we've got a fault with the protocol converter. These are now obsolete.
I'm looking into finding a new system of converting the Modbus RTU protocol commands to ESP protocol instructions for the GEM80. The functions generally take the form of requests for the state of A or B table data in the GEM for DCS running indication, or write information to the B tables as start or stop signals.
It appears we can use the Data Station Plus for this application. However the only Drivers I can find for the GEM80 listed are for J/K table master or slave. Can these drivers be used to read/ write data from the A & B tables?
I've spoken to the Red lion tech support and they seem to have been helpful and said they'll get back, but I thought you guys may know how easy it would be or have another solution in mind?
PS Excuse the looooong first post, but I thought the more background the better.
Port 2 of the GEM80 ribbon cable needs to communicate to our DCS system (in this case Honeywell TDC3000) via a Data Hiway Port using the Modbus RTU protocol. The GEM80 uses ESP protocol, and this previously was wired through an rs422-current loop converter and then an ESP-Modbus converter. The ESP-Modbus converter acted as a Modbus Slave to the TDC system and as a master to the GEM80.
We had a big plant upset recently which was finally traced back to a wire shorting across the back off the RS422 to RS485 converter PCB. Prior to this, all Port 2 operation stopped.
The GEM80 has been checked over, tested etc and is fully functioning. Port 1 is functioning fine too. However we believe we've got a fault with the protocol converter. These are now obsolete.
I'm looking into finding a new system of converting the Modbus RTU protocol commands to ESP protocol instructions for the GEM80. The functions generally take the form of requests for the state of A or B table data in the GEM for DCS running indication, or write information to the B tables as start or stop signals.
It appears we can use the Data Station Plus for this application. However the only Drivers I can find for the GEM80 listed are for J/K table master or slave. Can these drivers be used to read/ write data from the A & B tables?
I've spoken to the Red lion tech support and they seem to have been helpful and said they'll get back, but I thought you guys may know how easy it would be or have another solution in mind?
PS Excuse the looooong first post, but I thought the more background the better.