Schneider Electric PM870 Marine Instruments User Manual


 
© 2011 Schneider Electric. All Rights Reserved.
PowerLogic
TM
Series 800 Power Meter 63230-500-225A2
Appendix D—Advanced Power Quality Evaluations 3/2011
96
On-board alarm log entry for alarms: PM850 and the PM870 alarms are used to
perform some of the evaluations. If an on-board alarm log is enabled, an entry will be
made in the on-board alarm log when any of these alarms pick up or drop out.
NOTE: Enabling PQ Advanced evaluation does not guarantee that the on-board alarm log
or waveform files are enabled or properly configured to record these events. You should
consider your requirements and configure these files and the event captures triggered by
the various alarms to provide any additional data that would be helpful to diagnose or
document an exception to this standard.
Possible Configurations Through Register Writes
This section describes the changes you can make to configurations for the EN50160
evaluation through register writes in the PM850 and the PM870. Refer to “Advanced
Power Quality Evaluation System Configuration and Status Registers [EN50160 and
SEMI-F47/ITI (CBEMA)]” on page 99 for register assignments.
Select the first day of the week for evaluations. You can define the first day of the
week to be used for the EN50160 evaluations in register 3905.
Define the voltage interruption. The standard defines an interruption as voltage less
than 1% of nominal voltage. Because some locations require a different definition, you
can configure this value in register 3906.
Define allowable range of slow voltage variations.
The standard defines the allowable
range of slow voltage variations to be ±10% of nominal voltage. Because some locations
require a different definition, you can configure this value in register 3907.
Evaluation During Normal Operation
1
When the EN50160 evaluation is enabled, the PM850 and the PM870 evaluates metered
data under normal operating conditions, “excluding situations arising from faults or voltage
interruptions.” For this evaluation, normal operating conditions are defined as all phase
voltages greater than the definition of interruption. The standard specifies acceptable
ranges of operation for these data items.
This section describes how the EN50160 standard addresses metered data.
Power Frequency
EN50160 states that the nominal frequency of the supply voltage shall be 50 Hz. Under
normal operating conditions, the power meter will perform the valuation based on the
nominal frequency set on the meter.
for systems with synchronous connection to an interconnected system:
—50 Hz 1% during 99.5% of a year
50 Hz + 4 to -6% for 100% of the time
for systems with no synchronous connection to an interconnected system (for example,
power systems on some islands):
—50 Hz 2% during 95% of a week
—50 Hz 15% for 100% of the time
NOTE: The same range of percentages are used for 60 Hz systems.
Supply Voltage Variations
EN50160 states that, under normal operating conditions, excluding situations arising from
faults or voltage interruptions:
during each period of one week 95% of the ten minute mean rms values of the supply
voltage shall be within the range of U
n
10%.
all ten minute mean rms values of the supply voltage shall be within the range of U
n
+10% to -15%.
1
EN 50160:2000, Voltage characteristics of electricity supplied by public distribution systems.