Eradicated
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Hello everyone, I have a question about connecting to an S500 PLC.
I have been tasked with going to site and taking a backup of a program from an AB S500-series PLC (5/03 processor, actually a version by ProSoft with built-in Modbus Slave functionality).
I have never worked with these PLCs in the past and have very limited experience with Allen-Bradley in general.
I have the software (RSLogix500 Pro and RSLinx), so I should be good on the software side of things.
However, there are two ports on the PLC:
1) RS232 Port (standard DB9 connector)
2) DH485 Port (8P8C/RJ45 connector)
I know I could use either of these to connect to it, however the RS232 port is in use all the time, i.e. it is configured as a Modbus slave and a SCADA system uses it to retrieve data from the PLC. I might not get the permission to disconnect it during my site visit, so I might have to use the DH485 port.
Now the main questions:
a) Can I use a standard USB-to-RS485 converter to connect to the PLC using the DH485 port, or is it a different electrical interface? In other words, do I need a dedicated cable from AB or can I use a generic RS485 one (like ADAM)?
b) If I can use a generic RS485 adaptor, does anybody have a wiring diagram that I could use to connect to this port?
I would appreciate your help!
I have been tasked with going to site and taking a backup of a program from an AB S500-series PLC (5/03 processor, actually a version by ProSoft with built-in Modbus Slave functionality).
I have never worked with these PLCs in the past and have very limited experience with Allen-Bradley in general.
I have the software (RSLogix500 Pro and RSLinx), so I should be good on the software side of things.
However, there are two ports on the PLC:
1) RS232 Port (standard DB9 connector)
2) DH485 Port (8P8C/RJ45 connector)
I know I could use either of these to connect to it, however the RS232 port is in use all the time, i.e. it is configured as a Modbus slave and a SCADA system uses it to retrieve data from the PLC. I might not get the permission to disconnect it during my site visit, so I might have to use the DH485 port.
Now the main questions:
a) Can I use a standard USB-to-RS485 converter to connect to the PLC using the DH485 port, or is it a different electrical interface? In other words, do I need a dedicated cable from AB or can I use a generic RS485 one (like ADAM)?
b) If I can use a generic RS485 adaptor, does anybody have a wiring diagram that I could use to connect to this port?
I would appreciate your help!
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