Vemm Tec PTZ-BOX 5.0, Руководство пользователя

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PTZ-BOX 5.0 User manual, document edition: 13
13
1.2.12 Flow of energy
𝑄𝐸 =
𝑄𝑏×𝐻𝑠
3,6
(9)
where:
Qb – flow of gas volume at base conditions,
Hs – superior calorific value.
1.2.13 Flow of mass
𝑄𝑀 = 𝑄𝑏 × 𝑟𝑜𝑏
(10)
where:
Qb – gas volume flow at base conditions,
rob – gas density at base conditions.
1.2.14 Correction of flow from error curve of the gas meter
Switching of correction function is controlled by parameter CurveCorr , where:
Value 0 – correction function disabled,
Value 1 – correction function enabled.
Switching of correction function generates event “ Configuration changed ” which saves status of
function before and after modification.
Corrected flow
Qm from error curve of the gas meter is calculated with formula:
𝑄𝑚 = 𝑄𝑚𝑁 × 𝐹𝑄
(11)
𝐹𝑄 = 1 −
𝑓
′
(𝑄)
100%
(12)
𝑓
′
(𝑄) =
𝑓𝑃
𝑖+1
−𝑓𝑃
𝑖
𝑄𝑃
𝑖+1
−𝑄𝑃
𝑖
× (𝑄𝑚𝑁 − 𝑄𝑃
𝑖
) + 𝑓𝑃
𝑖
(13)
where:
QmN – uncorrected flow of gas volume at measurement conditions,
FQ – correction function, calculated basing on points FP1 ÷ FP10 and QP1 ÷ QP10 ,
fP
i+1
, fP
i
– values of gas meter errors at specific points,
QP
i+1
, QP
i
– values of flow for which error value was determined
WARNING: In accordance with standard EN 12405-1:2018 correction function can be used only when
gas meter at Qmin generates at least 10 pulses per second, this means that correction function can
be used in configurations of pulse inputs with
HF signal as main.
Below value of Qmin, correction function is not used, while above Qmax, value of correction function
is the same as for the one obtained for Qmax.
Correction is also used to calculate volume, energy and mass, parameters after correction are:
Vc , Vb , E, M .
Dimensions
Figure presents basic dimensions of PTZ-BOX 5.0 housing. During mounting, note that enough space
must be left in order to enable subsequent dismantling for maintenance or repair.