DANIEL 2234, Руководство пользователя

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MODEL 2234 DIGITAL FLOW COMPUTER
and the relay contacts to between 4.6 and 46.3 days, based on their rated
specifications.
It is recommended that the maximum long term pulse rate be
limited to one per second. This will yield a rated life upwards of 2315 days for
the electromechanical counter, and upwards of 115 to 1157 days for the relay
contacts. Calculate the required factors per the following example:
Assume the system contains two head meters, and that the average flow through
each meter is 300 LBH. Each meter flow is totalized in pounds (by using the
factory-programmed Line Volume Totalizing Factor of 10
o
). Each meter will yield
7200 pulses (pounds) per day (300 LBH x 24 hours ÷ 10
o
).
300 LBH x 24 hour/10
o
= 7200 Pulses (lbs.)
But more resolution is desired and a Line Volume Totalizing Factor of 10
-1
is
entered (totalizing in tenths of pounds). This will yield 72,000 pulses (tenths of
pounds) per day (300 x 24 ÷ 10
-1
) for each meter, or ten times the number of
pulses for a factor of 10.
300 (24)/10
-1
= 72000 Pulses (lbs.)
However, it is the station volume that drives the computer counter and relays so
the station volume rate is of the greatest consequence. In the preceding example
where the flow rate through each of two meters is 300 LBH, a factory programmed
Station Volume Totalizing Factor of 10
o
increments the counter 14,400 pulses
(pounds) per day (7,200 pulses x 2 meters); a factor of 10
-1
increments the counter
144,000 pulses (tenths of pounds) per day.
The Station Volume Factor of 10
-1
would yield a life of 1,389 days for the counter
and life of 69 to 694 days for the relay contacts.
SECTION 2
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