16
NT210 K
PRESSURE MEASUREMENT (P)
The pressure reading is made by a sensor placed under the head, through the specially provided opening.
The reading range of the sensor is -400 to + 500 mbar, the display negative values is made by indication DEP
and the relative value of depressure.
Setting for ALARM and TRIP contains just the positive value 0 to + 500 mbar.
When the pressure exceeds the set pre-alarm threshold (AL.1) by 10mbar the ALARM relay (AL1) switches, the
ALARM LED (AL1) comes on and P. is displayed. When the temperature exceeds the set pre-alarm threshold (AL2)
by 10 mbar, the TRIP(AL2) relay switches, the TRIP LED comes on and P. is displayed.
As soon as the pressure goes back to values equal to or lower than the threshold set for the
ALARM
and
TRIP
relays to switch, these relays deenergise and the relative LEDs switch off.
If the FPS function is activated and the set pressure increase speed is exceeded, the FAULT relay switches and
FPS is displayed on the screen. In this case the ALARM and TRIP functions are always active.
PRESSURE SENSOR ZEROING
To benefit from the precision offered by the electronic pressure sensor, we recommend the scale value is zeroed
before starting the transformer that must be cold and stable at ambient temperature (±20°C):
1) Press the MODE button and go to MAX mode
2) Press MODE again without releasing it for 6 seconds until the control unit is reset.
This operation will allow compensating for any reading tolerances due to differences in altitude or transformer filling
pressure.
For the system to be operating correctly the transformer must be cold.
LEVEL MEASUREMENT (L)
The level sensor measures quantity of oil into the sensor TPL503 case; the reading is expressed in three different
modes:
When the level reaches 0 (L2 threshold activated), alarm AL2 is triggered due to the minimum level being exceeded
and the TRIP relay switches.
Level value
Display
Gas formation / loss
FULL (3)
0 cm³/90 cm³
ALARM /AL1 (2)
100 cm³/180 cm³
TRIP /AL2 (1)
190 cm³ and more
By enabling the Alarm function or AL1 (YES), see programming on page 17, the alarm relay is triggered when the
level reaches the loss value of 100
cm³,
with NO the function is disabled.
By enabling the Trip function or AL2 (YES), see programming on page 17, the trip relay is triggered when the level
reaches the loss value of 190
cm³,
with NO the function is disabled.
The TPL503 must be installed so that the base end position corresponds to the minimum level below the
transformer cover, below which the warning must be triggered and the transformer tripped.
IMPORTANT WARNING
The stated oil volume/level values refer to the use of mineral oils with the following density: 888 Kg/m³ at the
temperature of 15°C (mineral oil general specifications).
The presence of air bubbles inside the transformer is identified as formation of gas which can cause a decrease in the
level indication and the activation of the Alarm and Trip signals.
