Dynasonics MFX Series Insertion MagProbe Flow Meter - Manual (Page 44)

Rev. 01/11
-3.10- MFX
4-20 TST - 4-20mA Output Test
4-20
Allows a simulated value to be output on from the 4-20mA output.
By incrementing this value, the 4-20mA output will transmit the
indicated current value. This feature can be utilized to confirm
connectivity with chart recorders, data acquisition systems or other
monitoring equipment.
ISO-MOD RATE PULSE (Value)
Flow at 0 Hz (FL 0H)
Flow at 2.5k Hz (FL 2.5KH)
The Rate Pulse Output Module is utilized to transmit information to
external counters and PID systems via a frequency output that is
proportional to system flow rate. Independent Zero and Span
settings are established in software using the Flow Measuring
Range entries. Output resolution of the module is 12-bits (4096
discrete points) and the maximum output frequency setting is
2,500 Hz. The module has two output modes, turbine meter
simulation and “open collector”. The turbine meter simulation
sources a non-ground referenced saw-tooth waveform with a
maximum amplitude of approximately 500 mV p-p. The open
collector output utilizes a 0.21 Ohm FET output that is rated to
operate at 100 V and 1 A maximum. If the open collector output is
utilized, an external voltage source and limit resistor must be
present. See Part 1 of this manual for connection information.
The FL 0H and FL 25KH entries are used to set the span of the
0 to 2.5k Hz frequency output. These entries are volumetric rate
units that are equal to the volumetric units configured as
Engineering Rate Units and Engineering Units Time Interval entered
on pages 3.11 and 3.12 of this manual.
PART 3 - KEYPAD CONFIGURATION
4-20mA Test
NOTE: The Maximum Rate may be set anywhere in the flow
measurement range of -30 to +30 FPS (-9 to +9 MPS). For
example: If bi-directional flow needs to be logged, set the MIN
RATE at a negative value and MAX RATE at a positive value.
Rate Pulse/
Freq
Rate Pulse
Span