What communications ports are available on a PM800 series meter and when should each be used
Below are the Communications ports available in PM800 series meter's;
1.The PM800 series meter base unit has a 2-wire RS-485 port (Comm 1).
2.The PM800 Remote Display Module has a 4-wire RS-485 port (Comm 2).
3.The PM800 Ethernet Communications Card (ECC) has a 4-wire RS-485 port (Comm 3).
When should each port be used;
1.The base unit 2-wire RS-485 port should be used to communicate directly with a PM800 if you have a 2-wire RS-485 daisy chain.
2.If you have a PM800 with a Remote Display module (4-wire RS-485) and you have a 4-wire RS-485 daisy chain, use this communications port, if you have a 2-wire daisy chain use the port on the base unit.
3.If you have a PM800 with an ECC and you intend to use the ECC card as a gateway, you will need to connect the downstream RS-485 wiring to the port on the ECC card. This port is configurable for 2-wire or 4-wire via dip switches. If you connect downstream devices to another port you will not be able to access them via the ECC.
a.Note: If you have a Remote Display module and an ECC connected to the PM800 base unit, the communications port on the Remote Display module is not functional.