Specifications
5
Instruction Manual
Section 2: Description and Specifications
LIQ-MAN-1066
April 2017
Input:
One isolated sensor input. Measurement choices of pH/ORP, resistivity/conductivity/TDS, %
concentration, total and free chlorine, monochloramine, dissolved oxygen, dissolved ozone, and
temperature. For contacting conductivity measurements, temperature element can be a PT1000
RTD or a PT100 RTD. Other measurements (except ORP) and use PT100 or PT1000 RTDs or a 22k
NTC (D.O. only).
power and load Requirements:
Supply voltage at the transmitter terminals should be at least
12.7 Vdc. Power supply voltage should cover the voltage drop on the cable plus the external load
resistor required for HART communications (250 Ω minimum). Minimum power supply voltage is
12.7 Vdc. Maximum power supply voltage is 42.4 Vdc (30 Vdc for intrinsically safe operation). The
graph shows the supply voltage required to maintain 12 Vdc (upper line) and 30 Vdc (lower line)
at the transmitter terminals when the current is 22 mA.
analog Outputs:
Two-wire loop powered (Output 1 only). Two 4-20 mA electrically isolated cur-
rent outputs (Output 2 must be externally powered). Superimposed HART digital signal on Output
1. Fully scalable over the operating range of the sensor.
Weight/Shipping Weight:
2 lbs/3 lbs (1 kg/1.5 kg)
1500
1250
1000
750
500
250
0
L
o
a
d
, ohms
with HART
communication
without HART
communication
12 18 24 30 36 42
545
ohms
1364
ohms
Power supply voltage, Vdc
HART option
FIGuRE 2-1. load/power Supply Requirements
