Woodward highprotec MRI4, Руководство пользователя

Страница: 150 / 727

System Alarms
System Alarms
Available Elements:
SysA
Please note that Power Protection and (Active/Reactive/Apparent) Power Demand is
only available within Protective Devices that offer current and voltage measurement.
Within the System Alarms menu [SysA] the User can configure:
General Settings (activate/inactivate the Demand Management, optional assign a signal, that will block the
Demand Management);
Power Protection (Peak values);
Demand Management (Power and Current); and
THD Protection.
Please note, that all thresholds are to be set as primary values.
Demand Management
Demand is the average of system current or power over a time interval (window)
. D
emand management supports
the User to keep energy demand below target values bound by contract (with the energy supplier). If the
contractual target values are exceeded, extra charges are to be paid to the energy supplier.
Therefore, demand management helps the User detect and avoid averaged peak loads that are taken into account
for the billing. In order to reduce the demand charge respective to demand rate, peak loads, if possible, should be
diversified. That means, if possible, avoiding large loads at the same time. In order to assist the User in analyzing
the demand, demand management might inform the User by an alarm. The User might also use demand alarms
and assign them on relays in order to perform load shedding (where applicable).
Demand management comprises:
Power Demand
Watt Demand (Active Power);
VAr Demand (Reactive Power);
VA Demand (Apparent Power); and
Current Demand.
150 MRI4 DOK-HB-MRI4-2E