2.2. Instrument rear terminals defination
.
Wire instruction
：
0V/220V
AC 220V input terminal (pH/ORP-5520)
0V/110V
AC 110V input terminal (pH/ORP-5510)
DC 24V input terminal (pH/ORP-5500)
（
Internal automatic recognition of polarity
）
24VA/B
EARTH
Electromagnetic compatibility earth protection terminal
Hi
High limit alarm control terminal blocks
Low
Low limit alarm control terminal blocks
T+
（
T+
、
T-
）
external feed under transmitting mode
T-/I+
public terminal under Transmitter /Instrument Mode
I-
(I+
、
I-) mA output terminal under Instrument mode
INPUT
Connect pH/ORP measurement electrode
（
Clear line
）
REF
Connect pH/ORP reference electrode
（
shielding
）
CELL-T
Connect temp. probe collect terminal
（
red line
）
GND
Connect temp. probe earth terminal
（
black line
）
NC
Empty terminal
4
