3
Chapter 5 Terminals
485R
485B
485B
PG
485A
L/+
NC
N/-
Terminal 485A: RS485 interface A
Terminal 485B: RS485 interface B
Terminal PG: Grounding
Terminal 485R: Matched Resistance
N/-: Neutral Wire
L/+: Live Wire
NC: Not Connection
Item
Description
Interface Terminals
485A
RS485 Communication
485B
Indicator Lights
PWR
power Indicator light
NET
network status indicator light
TXD
RS485 transmission indicator light
RXD
RS485 receiving indicator light
Indicator
Light Status
PWR
power Indicator light Flashing slowly after power on
NET
network status
indicator light
(examine SIM card
first and then signal
quality)
①
Flashing slowly after power on
②
Examine SIM card and signal quality
after power on for 10s. Indicator light
flashes
quickly
when
it
meets
requirements. Indicator light will be off
if it doesn’t meet requirements, which
means there is problem with signal
quality. Indicator light will always flash
slowly if it doesn’t examine the SIM
card, which mean there is problem with
the SIM card.
③
Indicator light will be always on after
connecting to the server.
④
Indicator light flashes once when
server receives the data from the DTU.
The flashing cycle is based on the
quantity of the transmitted data.
TXD
RS485 transmission
indicator light
The indicator light flashes when RS485
interface transmits data
RXD
RS485 receiving
indicator light
The indicator light flashes when RS485
interface receives data
