Data Flow Systems TCU800, Installation And Operation Manual, Page: 26 / 162

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C h a p t e r 3
Telemetry Interface
Connecting to a telemetry system provides the ability to remotely control the individually pumps with two software
switches: Override – (when tuned on) remotely forces a pump On, and Disable - (when tuned on) remotely forces a pump
Off, and effectively disables the the TCU from automatically controlling a pump. The H-O-A switch on the TCU must be
in the Auto position for either of these switches to have any effect, and both of these switch need to be in their off state for
the TCU to automatically control the pumps.
All three H-O-A switches must be in the “Hand” or “Off” position before any changes can be made to the TCU’s
configurations.
Local H-O-A control will always override any telemetry control.
Level Sensing Devices
The TCU features interfaces to several industry-standard level-sensing devices.
Discrete (Contact Closure) Devices
The TCU can accommodate digital-type devices such as contact closures, float switches, and pressure switches. Several
digital-type devices can be connected to up to six discrete digital monitoring points to control the operation of pumps. The
TCU is designed to handle simplex, duplex, and triplex configurations.
Analog Level-Sensing Devices
The TCU provides the option to monitor analog level-sensing devices, including ultrasonic, hydraulic pressure, and
pneumatic pressure transducers through an industry-standard 4-20mA / 0-5V interface. Any analog level-detection
transducer (self-powered or TCU powered) that supplies a 0-5V, 0-10V, or 4-20mA current signal can be used as an analog-
level input device and can be loop-powered using the provided 24VDC bias on the P2 connector.
A station can be controlled by:
1. Connecting an analog-type device to the TCU’s analog input terminals
2. Calibrating the maximum, minimum, and intermediate staging points
Internal Phase Monitor
A single- or three-phase 240 VAC power monitor is provided. An optional three-phase 480 VAC (using external resistors)
power monitor is also available (see “Appendix D: Parts List” for information on the 480 VAC Phase Monitor Kit). All
versions of the phase monitor detect phase loss and high and low line voltage phase faults. The three-phase 240 VAC and
optional 480 VAC power monitor also detect phase reversal. A fault of phase reversal, phase loss, or line voltage results
in an alarm and shuts down all automatically controlled pumps. The TCU has inputs for current transformers (CT) and
can support 3-phase 3-wire (delta) or 3-phase 4-wire (wye) setups. Active, reactive, and apparent power or energy can be
measured. The power factor can be measured when the CT inputs are used.