Dynasonics TFXP Series Transit Time Ultrasonic Flow Meter - Manual (Page 63)

Rev. 5/09
-3.25- TFXP
The 4-20 mA output can be configured to source current (internally
powered) or sink current (externally powered). The choice of sink or
source is configured at the factory to source current unless
otherwise instructed at the time the TFX is ordered.
The 4-20 mA output module interfaces with virtually all recording
and logging systems by transmitting an analog current that is
proportional to system flow rate.
Independent 4 mA and 20 mA span settings are established in
software using the Flow range entries. These entries can be set to
any flow values equivalent to -40 to +40 FPS (-12 to +12 MPS) for
the pipe the instrument is measuring. Output resolution of the
module is 12-bits (4096 discrete points) and the module can drive
up to 850 Ohms of load with its internal 24 VDC isolated power
source.
Internal Power Configuration (Current Source): This is the
factory default condition for the 4-20 mA output. In this
configuration the 4-20 mA output is driven from a +24 VDC
source located within the flow meter. The 24 VDC source is
isolated from DC ground and earth ground connections.
Figure 3.8 — 4-20 mA Output Wiring
PART 3 - KEYPAD CONFIGURATION