172-65256M-00 (VFM-T2) 7 Sep 2001
10
Calculating Total and Instantaneous Flow Rates
(1) Total: both cumulative and resettable total
Input Pulses
→
Frequency
→
Meter Factor
→
Frequency
→
To Individual
(2) Instantaneous: used only when input pulses have very small periodic variation.
The period of sample cycles is measured down to the unit of 1 ms, calculated
using the following equation and the result shown on the display.
3600
×
A
×
F
Flow rate per hour = b1 =
T (ms)
×
10
NOTE: A: number of sampling cycles
F: meter factor
T: interval of input pulse
b1
Flow rate per minute = b2 =
60
×
100
NOTE: The number of sampling cycles is determined such that the accuracy of the
instantaneous flow rate in full scale is held within
±
1% (100
≤
T
≤
200ms).
NOTE: It is designed so that when T
≥
5000 (ms), the instantaneous flow rate on the
display will show “0”.
NOTE: Set it so that sampling cycles × input period
≤
5000 (ms).
NOTE: Note that when “hard” dividing, the units for instantaneous flow rate are
modified.
Setting and Adjusting Jumpers, Switches and Volumes
l
The multifunction counter is preset to the customer specifications at the
factory before shipment. Unless it is necessary to change the preset
settings in the field, further adjustment should not be required.
NOTE: It is necessary to remove the internal components (motherboard) of the unit
when setting, modifying or adjusting jumpers, switches or volumes.
Hard
Soft
1/1,1/10 or 1/100
0.0001 - 1.9999
(1.000 set for input
of unit pulse)
1/1,1/10 or 1/100
µ
- CPU
Reduction
(Dividing)
Counter and
Output Unit
Reduction
(Dividing)
