Wigersma & Sikkema UNIGAS 300, Installation, Operating And Maintenance Manual

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Installation, operating and maintenance manual UNIGAS 300
DDG6004MHGB/08-2017/Rev.A2 Software version from M 1.3.40 and D 2.3.37 9
The following calibration characteristics can be modified using the UNITOOL software.
Input 1 LF 0.1 – 100000.0 impulses/m3
Input 1 HF 0.01 – 100000.00 impulses/m3
Input 2 0.1 – 100.0 impulses/m3
Input 3 0.1 – 100.0 impulses/m3
CO
2
0 – 30.00 mol %
H
2
0 – 10.00 mol %
N
2
0 – 50.00 mol %
d 0.5000 – 0.9000 - (at 0 °C)
H
s
14.00 – 48.00 MJ/m
3
(at 25°C)
Z/Z
bfix
0.5000 – 1.5000 -
Measuring interval p and t 5-25 s (set as standard at 25 s)
t
b
0-25.00 °C (set as standard at 0 °C)
p
b
800.00 – 1200.00 mbar (set as standard at 1013.25 mbar)
Z and Zb calculation on / off -
UNIGAS 300 will not accept a value outside the defined range.
Writing is protected by a calibration switch which is to be actuated during programming. Changes are stored
in the calibration log book, see 3.2.4.
3.2.1 Gas meter error curve correction
UNIGAS 300 features a function for error correction of a gas meter. This correction is possible if the high-
frequency impulse input on UNIGAS 300 is used. The error correction complies with standard EN12405-1 +A2.
The corrected volume is counted in counter Vc1. This will be discussed further in chapter 12.
If a low-frequency impulse or encoder input is used, the function of error correction of the gas meter is switched
off, counter Vc1 is equal to Vm1 and Vc1 cannot be set.
3.2.2 Handling conversion functions
Pressure, temperature and compressibility are measured and calculated every measuring interval. The
conversion depends on the signal input used:
•
LF: real-time conversion at descending flank of the gas meter impulse
•
HF: every second at presence of gas meter impulse(s)
•
encoder: every measuring interval directly following the measurement of pressure and temperature
and determination of compressibility.
3.2.3 Determining the flow rate and consumption
UNIGAS 300 determines the flow rate for input 1
•
Instantaneous flow rate:
o
LF: based on the interval between the two most recent impulses (Qb1_inst and Qc1_inst)
o
HF: based on the received number of impulses per second (Qb1_inst and Qc1_inst)
o
encoder: based on the measuring interval (Qb1_inst and Qc1_inst)
•
Consumption on the basis of an interval:
o
the measured volume for 5 min (Qb1_5 and Qc1_5)
o
a moving average of a series of 5-min values (Qb1_nx5 and Qc1_nx5)
o
consumption in a clock hour (Vb_60 and Vc_60).