SOMMAIRE
E 4
LOREME
12, rue des Potiers d'Etain - 57071 Metz
03.87.76.32.51 - Fax 03.87.76.32.52 - Email: [email protected] - [email protected]
Configuration via the front face
1) Thermal protection configuration
In this rubric, the user can set the different thermal protection parameters.
1.1) Nominal Voltage (mV)
The nominal voltage is the voltage trip point for the relay. It is used in the calculation of the trip time, and can be config-
ured from 0 mV to 200 mV. Usually this value should be set to the value of the measurement shunt caliber. For example
50mV for a 50 mV / 500 A shunt. The scale of the input is equal to 10 times the nominal voltage. For example, for a
nominal voltage = 50 mV, the input range will be 0/500 mV so the RPS23 will switch its input high caliber 0/2000 mV.
1.2) Nominal current (A)
This parameter is normally set to the current rating value of the measuring shunt. E.g. 500 A for a 50 mV / 500 A shunt.
It may also be configured to the value of
Unominal / Rshunt
if the configured nominal voltage is not the nominal shunt
voltage. It serves as a:
switching threshold for relay 3 (over current detection).
display scale for displaying the current measurement.
measurement scale for the calculation of the analog output.
1.3) Measure filter
In some noisy environment, it is necessary to filter the input signal. This parameter is the coefficient of the digital filter
included in the device. By increasing the value, the response time of the filter is increased and thus the response time of
the device. If the value is zero, there is no filtering. The parameter can be configured from 0 to 50 in 0.1 steps.
1.4) Thermal equations coefficients
The coefficients K, R, a, b, c used in the calculation of the thermal image are entirely configurable to adapt the relay
to quiet any protection curve. The relay uses the equation 1 for heating and the equation 2 for cooling:
1)
t = K x ( a / ((U / Unom)^b - 1) + c)
, for
(U/ Unom)^b > 1
.
2)
t = K x R / ((U / Unom)^b - 1)
, for
(U/ Unom)^b < 1
.
1.4.1) K coefficient
The K coefficient can be configured from 0 to 50 in 0.1 steps.
1.4.2) R coefficient
The R coefficient is used in the cooling equation. It can be configured from 0 to 100 in 0.01 steps.
1.4.3) a coefficient
The a coefficient can be configured from 0 to 100 in 0.001 steps.
1.4.4) b coefficient
The b coefficient is the power factor of thermal equations. It can be configured from 0 to 3 in 0.001 steps.
1.4.5) c coefficient
The c coefficient can be configured from 0 to 10 in 0.001 step.
See table next page for some examples of coefficient values for different thermal protection.
Remark:
RPS23 Timing accuracy:
Within ±5% or ±300ms whichever is greater. This is true when the “measure filter” is set to 0.
Increasing the “measure filter” parameter will increase the tripping time of the relay.
