Hach-Lange SI794 C User Manual - Manual (Page 100)

HOLD input Galv. separated (OPTO coupler)
Function Switches transmitter to HOLD mode
Switching voltage 0 ... 2 V (AC/DC) inactive
10 ... 30 V (AC/DC) active
CONTROL input Galv. separated (OPTO coupler)
Function Switch-over to second parameter set
Switching voltage 0 ... 2 V (AC/DC) Parameter set 1
10 ... 30 V (AC/DC) Parameter set 2
Output 1 0/4 to 20 mA, max. 10 V, floating
(galv. connected to output 2)
Process variable * Conductivity, resistivity, concentration,
or salinity
Characteristic Linear or logarithmic
Overrange * 22 mA in the case of error messages
Output filter * Low-pass, filter time constant 0 ... 120 s
Meas. error 1 ) < 0.3 % current value + 0.05 mA
Start/end of scale As desired within range
Minimum span LIN: 5 % of selected range
LOG: 1 decade
Output 2 0/4 to 20 mA, max. 10 V, floating
(galv. connected to output 1)
Process variable Temperature
Overrange * 22 mA in the case of temp error messages
Output filter * Low-pass, filter time constant 0 ... 120 s
Meas. error 1
) < 0.3 % current value + 0.05 mA
Start/end of scale * -20 ... 200 °C / -4 ... 392 °F
Span allowed 20 ... 320 K (36 ... 608 °F)
Alarm contact Relay contact, floating
Contact ratings AC< 250 V / < 3 A / < 750 VA
DC< 30 V / < 3 A / < 90 W
Contact response N/C (fail-safe type)
Alarm delay 0000 ... 0600 s
100
Specifications