AG3000 INSTRUCTIONS
Seametrics • 253.872.0284 Page 17 seametrics.com
CONFIGURATION
Cable Shield. In general, the cable shield and its bare drain
wire should be left unconnected at the user equipment end of
the cable to minimize “ground loop” problems.
Pulse Output Conguration. A pulse output is standard
on all models. Since this is an isolated output, the external
equipment must include a DC power source to regenerate the
pulse from the open-collector output (transistor equivalent
of a contact closure). A pull-up or pull-down resistor may
be needed if not included in the user equipment as shown
in the diagrams. Both the power source and resistor may be
supplied internally in some types of control and monitoring
devices. If not, as for most PLC discrete input modules, they
must be added externally at the module input terminals. The
pulse output rate in volume units/pulse can be set by the user
via the SETP tab on the meter’s setup menus.
Because the pulse output of an AG3000 meter is set by the
user, care must be taken to assure the output pulses do not
exceed the maximum frequency of the meter while also
ensuring a reasonable resolution.
K-factor: Remember that SETP is expressed in units totaled
per output pulse (G/P if using gallons) while K-factors are
expressed in pulses per gallon (P/G.) To determine K-factor
from SETP, divide 1 by SETP (if SETP is expressed in gallons.)
Conversely, 1 divided by the K-factor equals SETP
AG3000 meters that were initially congured as battery
powered units have a maximum output frequency of 150 Hz.
Those that were initially congured as powered units have a
maximum output frequency of 200 Hz.
Because all pulse outputs (SETP) are congured in (rate) units
totaled per pulse, all sizes of meters can be congured with
the same SETP values
For example, if your rate is chosen as gallons per minute
(GPM) the table below applies. If your rate is dierent, simply
use your rate label in place of (GPM.) The numerical values will
remain the same.
Pulse Units. The units of measure of SETP are independently
selectable and are not tied to rate or total. Upon change of the
SETP unit, the pulse output may take up to 10 seconds, or the
duration of one pulse (whichever is longer) to take eect.
If Pulse Output is Inconsistent. The DAMP lter may need
to be increased.
Pulse Width Timing. The unit and value of SETP must be
chosen to keep the duration between meter pulse outputs to
less than 500 seconds.
Pulse Timing in Battery Powered Units. The output pulse
width in battery powered units is short and varies with pulse
frequency. (See table)
SETP
Flow Rate at 1
Hz (GPM)
Flow Rate at
200 Hz (GPM)
PoweredMeters
Flow Rate at
150 Hz (GPM)
BatteryPowered
Meters
0.1 6 1200 900
0.2 12 2400 1800
0.3 18 3600 2700
0.4 24 4800 3600
0.5 30 6000 4500
0.6 36 7200 5400
0.7 42 8400 6300
0.8 48 9600 7200
0.9 54 10800 8100
1.0 60 12000 9000
Lowerfrequencyoutputpulses(1pulseforsomeparticular
numberofgallons)canalsobeset.
Any output frequency can be determined by:
Rate (units/minute) ÷ SETP (units/pulse) = pulse/minute
Hz = pulse/minute ÷ 60 seconds / minutes
For reference/comparison only
K-factors and the equivalent SETP values for old style
WMX units are shown below.
WMX 4” 6” 8” 10” 12”
K-Factor 16.36 6.31 3.34 2.15 1.53
SETP 0.06* 0.16 0.30 0.47 0.65
*NotethatontheAG3000youwouldneedtochoose
aSETPvalueof0.1forthe4”.
Output Pulse Width of Battery Powered Units
Output Pulse Frequency
Output Pulse Width as a Percentage of
the Pulse Period
(Pulse period = 1000 milliseconds/frequency)
Zero to 1 Hz
Multiply the pulse
period by 0.01
= Output Pulse
Width (ms)
1 to 20 Hz
Multiply the pulse
period by 0.05
= Output Pulse
Width (ms)
20 to 100 Hz
Multiply the pulse
period by 0.1
= Output Pulse
Width (ms)
100 to 150 Hz
Multiply the pulse
period by 0.15
= Output Pulse
Width (ms)
Example:Iffrequency = 20 Hz thenthe pulse period =50 milliseconds and
pulsewidth=(.05x50milliseconds)=2.5ms
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