Data Flow Systems TCU800, Installation And Operation Manual

Page: 47 / 162

37
S e t u p
These six inputs, plus the AUX_IN (P2-12) and ALM_SIL (P2-13) inputs, are internally connected to IN_COM_2 (P2-14).
All eight of these inputs must be biased with the same voltage source.
Simplex stations use input terminals LOW_LVL (P2-6), OFF_LVL (P2-7), LEAD_LVL (P2-8), and HIGH_LVL (P2-11).
Duplex stations add input LAG1_LVL (P2-9).
Triplex stations add input LAG2_LVL (P2-10).
It is recommended that you use LOW_LVL and HIGH_LVL inputs. However, HIGH_LVL can be omitted but should be
disabled in the configurations, which will allow the input to be used to detect other signals. If a LOW_LVL is not used, the
LOW_LVL function must be disabled in the TCU’s configuration as the TCU will not function and control pumps unless
this is done.
1. Connect the bias source to one side (line side) of the floats or pressure switches being monitored and the bias return to
the IN_CON_2 (P2-14).
2. Connect the other side (load side) of the float or switch to the corresponding input terminal on the TCU. Use voltage
dropping resistors if required.
Monitoring Circuit for a Contact-Closure Level Detection Device
The voltage-dropping resistors are only necessary for input voltages greater than 30VDC/AC. It is not
recommended to use voltages higher than these for typical float contacts.