Photoelectric direct reading remote water meter is a common electronic remote water meter. Some users report that communication failure will occur during use. What are the reasons for communication failure?
The reasons for communication failure can be briefly summarized as follows: (1) wiring error (2) the protocol, baud rate and other technical parameters are incorrect during communication (3) the water meter module is broken.
Therefore, to solve this problem, we need to understand the following issues:
What is the wiring method of the photoelectric meter? m-bus or RS485? Solution: if it is m-bus connection, the water meter comes out with two wires, directly connected to the bus or test equipment regardless of positive and negative polarity; if it is RS485 connection, the water meter comes out with 4 wires , Respectively, "red-power positive, black-power negative, yellow-positive signal, blue-negative signal" Please verify the wiring.
Did you specify the technical parameters when buying the watch (respectively the protocol, baud rate and verification method, etc.)? Solution: If technical parameters are specified, test the water meter according to your technical parameters. If no technical parameters are specified, test as follows:
(1) 188 protocol default baud rate is 2400bps, 8 data bits, 1 stop bit, even parity.
(2) The 645 protocol default baud rate is 1200bps, 8 data bits, 1 stop bit, even parity.
(3) The default baud rate of the modbus protocol is 9600bps, 8 data bits, 1 stop bit, and no parity.
Have tried the above methods, the water meter still can't communicate? Solution: The module of the water meter itself is faulty. Replace the spare water meter, and send the problem table to the manufacturer for repair.
Further reading: What is included in the wired remote transmission solution?
The wired remote transmission solution consists of a wired remote ultrasonic water meter, M-bus (RS 485) communication bus, M-bus (RS 485) data concentrator, and data center.
The M-bus (RS 485) data concentrator communicates with the remote water meter with a built-in M-bus (RS 485) communication module via the M-bus (RS 485) communication bus, and communicates with the data center via the GPRS module.