Novatek-electro OM-310, Руководство пользователя

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NOVATEK-ELECTRO
ОМ-310
1. DESCRIPTION AND OPERATION
1.1 APPLICATION
1.1.1 OM-310 power limiter is designed for the following applications:
- load protection at poor parameters of the mains;
- complete load cutoff in case if watts input exceeds the main threshold within the user-set time period;
- partial load cutoff in case if watts input exceeds the additional threshold within the user-set time period;
- measurement and indication of 3-phase electric circuit (delta voltage and mesh voltage RMS values; positive
phase, negative phase and zero phase sequence voltages; phase currents RMS values; input wattage of active
power, wattles power, apparent power, power factor (cos
ϕ
))
- fault warning;
- remote load on and off via RS-232/RS485 interface or and external switch.
OM-310 provides for operation under loads ranging from 2,5 kW to 30 kW with use of integrated current transfor-
mers, and up to 350 kW at use of external current transformers, including when in networks with insulated neutral.
OM-310 device provides the following types of load protection:
-
when the mains voltage is of poor quality (impermissible voltage surges, phase loss, incorrect phase se-
quence and phase "coincidence", phase/line voltage imbalance);
-
when maximum specified current in any load phase is exceeded;
- against “ground” leakage currents;
For each separate type of protection, the unit allows to enable or disable automatic load reset (further: AR)
OM-310 provides electric equipment protection by means of a magnetic starter (contactor) coil control.
Using
OM-310 the user has possibility
t
o choose functionality of additional relay and use it for following operations:
-signalization emergency situations
- contactor connection of additional loading
-as time relay
-signalization of reactive power excess
-signalization of active power excess
Communication
ОМ
-310 provides for:
- control and parameters transfer via RS-485 interface according to MODBUS protocol,
- control and parameters transfer via RS-232 interface.
N o t e: Simultaneous use of RS-485 and RS-232 is not possible.
Interaction of PC and OM-310 is possible via "OM-310 Control Panel” Software that can be downloaded from
the “Novatek-Electro” website (http://www.novatek-
electro.com/production_ом.htm
).
OM-310 Control Panel software is dedicated for monitoring status and retrieving data from OM-310 devices via stan-
dard communication interface (RS-232 or RS-485). The Software allows for saving (loading) various OM-310 settings,
retrieving data and saving them for further research. The user can view saved data in a graph, while comparing pa-
rameters.
The CP graphic environment allows for real-time viewing the current status of various OM-310 parameters.
The flexible interface design allows tuning it to any user’s preferences.
1.1.2 OM-310 application limitations and proper selection of parameters
1.1.2.1 Use of integrated current transformers.
Attention! OM-310 cannot be used for protection of load with wattage over 30 kW.
When measuring load currents from 63A to 300A, the measurement error does not exceed 5%, while at currents
over 320A, the current transformer core saturation starts, and the measurement error increases rapidly. Regardless
In spite of the actual current value, the current measured by OM-310 will not exceed 400A. Setting up certain pro-
grammable parameters (maximum current protection) without regard to current transformers saturation will make
protection tripping impossible.
For example, at “

”=50 (load rated current),



=0 (ratio of independent delay current protection),



=9
(maximum current protection tripping), the maximum current protection would have tripped at current value of 450
А.
Due to current transformer saturation, the measured current value will not exceed 380-400A, even in case of a short
circuit fr
om the load side, and currents of over 1000A, and, therefore, ОМ
-310 will not de-energize the load. In such
case (“

”=50) the user shall set the overcurrent tripping ratio to not more than 6.
1.1.2.2 Use of external currents transformers.
In case of tested standard transformer samples, the core saturation took place at 4-5 times the rated current
value. Therefore, to provide for proper functioning of ОМ
-310 protections, one should select external transformers
with rated current value exceeding the rated load currents twice and more, or choose parameters considering the
saturation.