Trumeter 877 Series, Manual

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20
Operation
Base Unit
The base unit measures the time between pulses generated by a process.
The display can be programmed to show either Rate or process time (Tau), by setting the
Display parameter.
The display can be programmed to read in any units by setting the Display Decimal Point,
Scaler and Scaler Decimal Point parameters.
The unit can be programmed to average the process time or rate over a number of
pulses, by setting the Update Time parameter. The display will not update until the first
pulse after the update time.
The display will reset to zero, if no pulses are received within the time set in the
Zero Time parameter. This will determine the lowest rate that can be measured.
Scaler Calculations
NOS = Number Of Seconds in time unit (1=seconds, 60=minutes, 3600=hours etc)
PPI = Pulses Per Item (revolution, metre, litre, machine cycle etc)
DPF = Decimal Point Factor (from table below)
Display Decimal Point DPF
10000 1
1000.0 10
100.00 100
10.000 1000
1.0000 10000
for Rate:
Scaler = NOS x DPF
PPI
for process time (Tau):
Scaler = PPI x DPF
NOS
Note:
eg. Scaler = 1.2345
first set Scaler Decimal Point to 1.0000
eg. Scaler = 12.345
first set Scaler Decimal Point to 10.000
etc