Installation – Hach-Lange RTC113 ST-Module User Manual
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Installation
3.4 Connection to the automation unit on the plant side
The one-channel and two-channel versions of the ST-Module are equipped with various
modules that must be connected to the plant automation system.
•
The feed flow rate must be provided to the ST-Module as a 0/4 to 20 mA signal.
•
The polymer flow rate must be provided (on both versions) to the ST-Module as a
0/4 to 20 mA signal.
•
The status signal of the thickened sludge pump (on/off) must be a digital input signal
(24 V/0 V).
•
The polymer pump can be operated in pulse/pause mode (PWM).
•
The status signals and fault indications are output as 0 V/24 V signals.
•
Measurement errors are shown 5 minutes after the error occurs. In the event of a new
startup (return of power supply), the unit is set back to ON (24 V) after approximately
1 minute and 40 seconds if there are no measurement errors.
•
In the event of a new startup (return of power supply), the RTC operating signal is set
back to ON (24 V) after approximately 1 minute and 25 seconds.
Table 3 Connections for the 1-channel RTC113 ST-Module
Module
Name
Connection Signal
Function
2x digital input
KL1002
1
Input + 24 V/0 V
Status of thickened sludge pump (on/off)
2
Source + 24 V
24 V for relay
4x digital output
1
KL2134
1
+24 V/0 V
Polymer pump on/off (24 V/0 V)
5
+24 V/0 V
Closed-loop control of the feed flow rate
active/inactive (24 V/0 V)
4
+24 V/0 V
Input signals OK (24 V), input signal faulty (0 V)
8
+24 V/0 V
RTC operational (24 V), RTC faulty (0 V)
2x analog output
KL4012
1(+) - 3(-)
0/4 to 20 mA
Output of the polymer pump flow rate
5(+) - 7(-)
0/4 to 20 mA
Output of the feed flow rate
1x analog input
KL3011
1(+) - 2(-)
0/4 to 20 mA
Input of the feed flow rate
1x analog input
KL3011
1(+) - 2(-)
0/4 to 20 mA
Input of the polymer flow rate
Bus termination
KL9010
Bus termination
1
Ground to connection 3 and 7 or to the supply voltage connections
Table 4 Connections for the 2-channel RTC113 ST-Module
Module
Name
Connection Signal
Channel Function
4x digital input
KL1002
1
Input + 24 V/0 V
1
Status of thickened sludge pump (on/off)
2
Source + 24 V
1
24 V for relay
5
Input + 24 V/0 V
2
Status of thickened sludge pump (on/off)
6
Source + 24 V
2
24 V for relay