U
SER
'
S
G
UIDE
___________________________________________________________________________
U370EN-1.1___________________________________________________________________________4
PIN
SIGNAL
1
not used
2
TX
3
RX
4
not used
5
ground for RS 232
6
not used
7
not used
8
not used
9
not used
RS485
The pin assignment of the RS485 serial interface connector of the
PTB220TS/CASE is as following:
PIN
SIGNAL
1
not used
2
RS485 HI
3
not used
4
not used
5
RS485 LO
6
not used
LED Indicators
There are four
LED
indicators in the back plate of the tilting frame. The
LED
indicators inform the user of operating status of the barometer.
The green
PWR
led indicates that the PTB220 barometer is switched
ON.
The red
BATT
led indicates that the internal lead battery is being
recharged. When the battery is fully charged the led returns dark.
The yellow
TX / RX
leds indicate that there is activity in the serial line.