Manual

Chapter 5 Configuring the EM920
Configuring Recorders
EM920 Power Quality and Revenue Meter 107
The following table can help you calculate an estimated file
size for conventional log files when planning your memory
allocation. The actual file size will normally be a bit bigger.
File Record Size, Bytes File Size, Bytes
Event Log 20 Record size × Number of records
Conventional Data Log 12 + 4 × Number of parameters Record size × Number of records
EN50160 Compliance Statistics,
Data log #9
148 × 12 channels Record size × Number of records
EN50160 Harmonics Survey,
Data log #10
220 × 3 channels Record size × Number of records
Waveform Log 1068 × Number of Channels Record size x Number of series
(events) × Number of records per
series
EN50160 Power Quality Log 32 Record size × Number of records
Fault Log 40 Record size × Number of records
The meter memory is pre-configured at the factory for
common data trending, billing, power quality and fault
recording applications as shown in the following table.
No. File Size,
Bytes
Channels Number
of
Records
Number
of Events
Factory-set Configuration
1 Event log 21504 1000 1000
2 Data log #1 439296 5760 5760 Instrumentation 15-min data
trending for 60 days
3 Data log #2 439296 5760 5760 Instrumentation 15-min data
trending for 60 days
10 Data log #9 102400 12 56 56 EN50160 compliance statistics
11 Data log #10 38912 3 56 56 EN50160 harmonics survey
13 Data log #12 600064 11520 11520 15-min energy load profile for
120 days
14 Data log #13 208896 4320 4320 Fast fault RMS trend
15 Data log #14 191488 4320 4320 Fast PQ RMS trend
16 Data log #15 61440 20 24 24 Monthly Billing/TOU profile for
24 months
17 Data log #16 116736 20 120 120 Daily Billing/TOU profile for 120
days
18 Waveform log #1 3083264 6 480 120 PQ and fault waveforms:
32 samples/cycle × 64 cycles
19 Waveform log #2 776192 6 120 60 PQ waveforms:
128 samples/cycle × 64 cycles
20 Waveform log #3 518144 4 120 60 Fast transient waveforms:
1024 samples/cycle × 1 cycle
27 EN50160 Power
Quality log
33792 1000 1000
28 Fault log 41984 1000 1000
NOTE
The meter automatically performs de-fragmentation of the
memory each time you re-organize your files. This prevents
possible leakage of memory caused by fragmentation.
Depending on the data stored in the memory, it may take
from seconds to a couple of minutes.