DEMA CPM 310 G, User Manual

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IEC Thermal Overload Protection Curve
IEC Thermal Overload Protection formula and sample curves according to this formula are given below.
Formula characteristic is determined by the T
e
, k, I
θ
, %θ
p
and %θ
trip
parameters. When setting ranges for these
parameters are considered, it is calculated that CPM 310 G relay can run 1,540,000 unique IEC Thermal
Overload Protection curves; for its impossible to demonstrate all of the curves on a chart, sample curves are
given on the below chart to express an overview of the characteristic.
□
𝑡 = 𝑇
𝑒
×
log
e
[
(
𝐼
𝑘 × 𝐼
Θ
)
2
− %Θ
𝑝
(
𝐼
𝑘 × 𝐼
Θ
)
2
− %Θ
𝑡𝑟𝑖𝑝
]
t Trip time delay (minute).
T
e
Thermal Constant (minute); setting range: (1-200) m, in 1m steps.
k Trip Threshold Translation Constant (-); setting range: (1.00-1.50), in 0.01 steps.
I RMS value of load current (A).
I
θ
Set current (A); setting range: (0.10-3.20) In, in 0.01I
n
steps.
%θ
p
Overload Pre-heating (%); setting range: (50-200) %, in 1% steps.
%θ
trip
Overload Trip Threshold (%); setting range: (50-200) %, in 1% steps.
□