QALCOMET HEAT 1, Руководство пользователя

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Heat meter calculator QALCOMET HEAT 1 PEQMH1V01
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4. OPERATING PRINCIPLE
The calculator QALCOMET HEAT 1 is a sub-assembly of a heat meter, together with standard
flow sensors, temperature and pressure sensors.
Flow sensors, based on ultrasonic, electromagnetic or mechanical measurement principle, can be
used for flow rate measurement. Suitable types of flow sensors are listed in Table 5. Other types of flow
sensors can also be used if they correspond to requirements provided in paragraph 2.
Flow sensors are connected to the calculator using two-wire or three-wire cable. Flow sensors can
be powered from calculator power supply, from own internal battery or directly from mains power source.
Operation principles of flow sensors are described in appropriate technical documents, provided together
with flow sensors.
Heat meter calculator QALCOMET HEAT 1 is multi-channel programmable measurement
device. It can measure and record simultaneously parameters from 2 heating systems up to 5 temperature
measurement channels, up to 5 flow measurement channels and up to 2 pressure measurement channels.
The user may select one of eight possible measurement scheme, depending on measurement
system configuration and in justice to the heating (conditioning) scheme type.
Sensor output signals are passed to appropriate calculator’s inputs:
- flow rate values are transmitted as pulses,
- pressure values are transmitted as limited current,
- temperature values are transmitted as resistance alterations.
Later analog signals are converted into digital code and used by microprocessor to calculate flow
rate, temperature and pressure on relevant measurement channel.
Consumed fluid volume corresponds to received number of metering pulses, taking into account
pulse value. Consumed fluid mass is calculated by integrating volume alterations multiplied by relevant
fluid density, taking into account measured fluid temperature and measured (or preprogrammed) pressure.
Heat energy is calculated using formulas provided in Table 1.
The following pressure values can be used for calculations:
- programmed individually for each particular heating system
- practically measured (1-st pressure channel corresponds to the supply pipe, 2-nd
–
return pipe).
Possible heat energy calculation algorithms (individual for each measurement system):

standard unidirectional flow measurement, energy is calculated without any
restrictions,

special unidirectional flow measurement, energy is calculated:
a) when flow rate exceeds programmed maximum allowed value -
according to programmed rated maximum value for appropriate flow
channel;
b) when flow rate is under programmed minimum allowed value -
according to programmed rated minimum value for appropriate flow
channel;
c) when temperature difference is under programmed minimum
allowed value
–
according to programmed rated minimum temperature
difference Θ1
-
Θ2 (for the 1
-
st heating system) or Θ3
-
Θ4 (for the 2
-nd
heating system).
Error code is generated when parameter values exceed given limits. Also, in
that case the device stops calculating working time, and calculates error
duration.

winter/summer flow in 2-nd channel is measured in both directions, energy is calculated
taking into account flow direction without any limitations (only for “A”
measurement scheme
–
see Table 1).
Flow in 2-nd channel is recorded separately
–
di
rect inlet flow as (“2”) and
return flow in opposite direction -
as (“
-
2”).
Information on flow direction is received using separate logical signal, connected to 4-th flow input. In
this case, only 1-st, 2-nd and 5-th flow sensors can be used for flow measurement.