Hach-Lange SI794 D User Manual User Manual
Page 91
Temperature input
NTC 22 kohms / NTC 30 kohms*
2-wire connection, adjustable
Measuring range
-20.0 ... +150.0 °C / -4 ... +302 °F
Adjustment range
10 K
Resolution
0.1 °C / 1 °F
Measurement error
1,2,3
< 0.5 K (<1 K at > 100°C)
HOLD input
Galvanically separated (OPTO coupler)
Function
Switches transmitter to Hold mode
Switching voltage
Inactive 0 ... 2 V (AC/DC)
Active 10 ... 30 V (AC/DC)
CONTROL input
Galvanically separated (OPTO coupler)
Function
Control input for automatic cleaning system
Switching voltage
Inactive 0 ... 2 V (AC/DC)
Active 10 ... 30 V (AC/DC)
Output 1
0/4 to 20 mA, max. 10 V, floating
(galv. connected to output 2)
Process variable *
O
2
saturation/O
2
concentration
Overrange *
22 mA in the case of error messages
Output filter *
Low-pass, filter time interval 0 ... 120 s
Meas. error
1
< 0.3 % current value + 0.05 mA
Start/end of scale
Configurable within selected range
Span allowed
5 ... 500 % / 0.5 ... 50 mg/L (ppm)
Output 2
0/4 to 20 mA, max. 10 V, floating
(galv. connected to output 1)
Measured variable
Temperature
Overrange *
22 mA in case of temp error messages
Output filter *
Low-pass, filter time interval 0 ... 120 s
Measurement error
1
< 0.3 % current value + 0.05 mA
Start/end of scale *
-20 ... +150 °C / -4 ... +302 °F
Span allowed
20 ... 170 K (68 ... 338 °F)
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