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NOVATEK-ELECTRO
ОМ-310
Figure 1.5
- Principle of protection with dependent time delay
Graphs for the protection operation time constant equal to 1 sec (“
” parameter) are provided in Appendix 1.
When a different value for time constant is set, the protection trip time changes proportionally to the time constant
(for example, at “
”=10 seconds the protection trip time at the same current ratio will increase 10 times).
1.2.6.4 Ground fault protection:
- is activated when earth fault current reaches the trip threshold (“
”);parameter);
- the load relay opens if the earth fault current crosses the trip threshold within T time period (“
” parameter).
1.2.6.5 Voltage based protection
In voltage-based protections, before load energizing, OM -310 checks for corresponding threshold settings, and,
depending on their value, either permits or prohibits load energization; after load energization the voltage control is
retained.
Voltage-based protections include:
- protection for minimum line voltage (it trips when at least one of the line currents is less than the threshold set-
ting (“
” parameter) within time specified by “
” parameter);.
- protection for maximum line voltage (it trips when at least one of the line currents is greater than the threshold
setting (“
” parameter) within time specified by “
” parameter);
- protection for line voltages imbalance ( trips if difference between
RMS
line voltages exceeds the set threshold
(“
” parameter) within time assigned by “
” parameter).
1.2.6.6 Protection based on phase sequence order trips in case of phase sequence order fault or phase coin-
cidence it opens the load relay and locks its further operation.
1.2.6.7 Starter unit operability control (at
=1). If currrents are present when the relay is open, the starter is
considered faulty. Further OM-310 operation is locked. The alarm reset can be performed by de-energizing only.
1.3 PRODUCT PACKAGE CONTENTS
The product package contents are shown in Table 1.7.
Table 1.7
- Product package contents
Description
Abbreviation
ОМ
-310
ОМ
-310
Differential current transformer (zero sequence transformer)*
Cable for communication with PC via RS-232*
KC-01
Transmitter cable for communication with PC via USB*
KC-USB-01
* - supplied optionally
1.4 EQUIPMENT FEATURES AND OPERATION
ОМ
-310 is a microprocessor-based digital device that provides a high degree of reliability and accuracy. The
device doesn't need any auxiliary supply: it's self-powered by the voltage to be monitored.
ОМ
-310 device is equipped with three built-in CTs, through which power phase mains are conducted.
2. INTENDED USE
2.1. SAFETY
All connections must be performed on dead device.
2.2 ОМ
-310 DEVICE CONTROL
2.2.1 Control Modes
OM-310 has five control modes:
-keyboard lock level;
- mode with minimal number of setting parameters (further on referred to as MMSP);
-user level;
-service engineer level;
- remote control.
In all operation modes the following features are available:
- viewing measured and displayed parameters
(Tablе 1.4). Scrolling through parameters list is performed by
DOWN and UP buttons;
-
faults log view (п.2.4.8).
