Novatek UBZ-304, Руководство по эксплуатации

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UBZ-304
NOVATEK-ELECTRO
I/Iн –
current ratio relative to rated one;
Т/Т2 –
the actual response time relative to T2 (response time when double overload).
Figure 3.4
–
Current-time characteristic
3.4.8 Windings overheating protection
3.4.8.1 The first input protection:
–
when working with motor built-in temperature transmitters (parameter
“Temp S1 Type”=”R>1
.
7”)
protection
is enabled when the transmitter resistance will be more than 1700 Ohms. Set-point
“Temp S1 Off M”
is not
used: short-circuit and breakout of the transmitter is not controlled;
– when working with transmitters of PTC type (1kOhm at 25°C) (“Temp S1 Type” = PTC parameter),
protection is enabled and stops the motor when the monitored temperature is more than the set-point
(
“
Temp S1 Off M
”
parameter).
When working with PTC type transmitters, protection defines the cases of breakout and short circuit of the
transmitter:
–
the breakout at the temperature higher than 100
°
C;
– short circuit at the temperature less than minus 45°
C.
3.4.8.2 The second input protection:
–
it is enabled when the controlled temperature is higher than set-point;
–
it has two independent set-points: the alarm set-point
(“Temp S2 Alarm”
parameter) and the set-point
for the motor is off
(“Temp S2 Off M”
parameter).
Protection determines the cases of breakout and short circuit of the temperature transmitters:
–
breakout at temperature of more than
220°C;
–
short circuit at temperature of less than minus
45°C.
On the second input the protection is operated with temperature transmitters of Pt100 type (platinum type for 100
Ohm at 0°C) or Ni100 (Ni120) (Nickel type for 100 Ohm (120 Ohm) at 0°C) in accordance with the standards of IEC
60751 and DIN 43760.
3.4.9 Voltage protection
In UBZ voltage protection before enabling the load it is necessary to check the corresponding set-points and
depending on their value, the load relay enabling will be permitted or disabled; when the motor is on, the voltage
control is fulfilled, but the decision relative to disabling is made according to currents.
N o te
–
UBZ considers the motor is switched off if the load relay is off (operating in star-delta mode the load
relay and functional relay are disabled), or if the load relay is on, the motor currents are less than 10 percent of the
motor rated current.
The voltage protections are the following:
–
at minimum line voltage (it is enabled if at least one of the line voltages is less than the set-point
(“Umin
tresh”
parameter) within the time specified by
“Umin delay”
parameter);
–
at maximum line voltage (it is enabled if at least one of the line voltages is more than the set-point
(“Umax
tresh”
parameter) within the time specified by
“Umax delay”
parameter);
–
during line voltages imbalance (it is enabled if the difference between effective values of the line voltages is
more than the set-point (
“Uimbal tresh”
parameter) within the time specified by
“Uimbal delay”
parameter).
3.4.10 Phase sequence protection (
“Correct phase”
parameter) is enabled in case of improper phase
sequence; it disables the motor and blocks its further operation.
3.4.11 Network power frequency drop protection is enabled, if the network power frequency is less than the
set-point
(“Frequency Min”
parameter) within the time specified by
“FreqMin d
e
lay”
parameter.
3.4.12 Network power frequency rise protection is enabled, if the network power frequency is higher than the
set-point
(“Fr
e
quency Max”
parameter) within the time specified by
“FreqMax delay”
parameter.
3.4.13 Protection for minimum resistance of motor winding insulation