Question 1

What do the LEDs on a Wiman gateway mean?

Accepted Answer

PWR shows power, GSM / CON shows network and server connection state, TXD flashes when the gateway transmits a query, and RXD flashes when a reply arrives. Reading the four together tells you in seconds whether the problem is power, network, or the Modbus side — the interactive guide plays every pattern live.

Question 2

Why is TXD blinking but RXD staying dark?

Accepted Answer

The gateway is asking, but no device is answering. That points at the RS-485 side: A/B swapped or broken wiring, wrong baud rate or parity, wrong slave ID, or the meter simply powered off. It is the classic no-reply signature on a Modbus RTU bus.

Question 3

What does the GSM / CON LED tell me?

Accepted Answer

Its blink pattern walks through the connection stages — searching for network, registering, and connected to the server. A pattern that never settles means the gateway is not reaching the network or server: check antenna, SIM / APN settings, signal strength, and the server endpoint.

Question 4

How do I diagnose a SIM problem from the LEDs?

Accepted Answer

A gateway that never gets past the network-search pattern usually has a SIM issue — not seated, not activated, or wrong APN. Reseat the SIM, confirm the APN configuration, and check signal strength at the installation point.

Question 5

What should I check first when no LED is on?

Accepted Answer

Supply voltage and polarity. Verify the DC supply at the gateway terminals; no PWR LED almost always means a power problem, not a firmware one.

Gateway LED Patterns

Gateway LED Patterns