SATEC EM920 Operation Manual - Manual (Page 17)

Chapter 2 Operating the EM920
Device Diagnostics
EM920 Power Quality and Revenue Meter 17
Device Diagnostics
Device diagnostic messages may appear as a result of the
EM920 built-in diagnostic tests performed during start-up and
device operation.
A blinking diagnostics indicator is shown on the display
whenever there are diagnostic messages. See
Status
Indicators in Chapter 3 for information on diagnostics
indicators. See Device Diagnostics Display in Chapter 3 on
how to inspect the meter diagnostics messages from the
display.
The device diagnostics status is stored in a non-volatile
register, which may be inspected and cleared from the meter
display, via the supplemental PAS software, or from a user
application. See
Viewing and Clearing Device Diagnostics in
Chapter 6 on how to clear the device diagnostics status in
your meter.
All diagnostic events with time stamps are also recorded in
the meter Event log and can be inspected via PAS (see
Retrieving Recorded Files in Chapter 7).
In the event of a device fault, check the fault reason and
clear the device diagnostics. See
Device Diagnostic Codes in
Appendix H for the list of diagnostic messages and their
meanings. In the event of a time fault, update the device
clock. In the event of a configuration reset, check the setup
affected by the fault via the device Event log, and then verify
the setup data.
Hardware failures are normally non-critical recoverable faults
that do not cause a system failure but may cause data loss.
Hardware failures are often caused by excessive electrical
noise in the region of the device. If the device continuously
resets itself, contact your local distributor.
Device Fault Alarm
The EM920 provides a global "DEVICE FAULT" event flag that
is asserted all the time while one of the diagnostic events
exists. It can be monitored via a setpoint (see
Using Control
Setpoints in Chapter 5) to give a fault indication through a
relay output. If the alarm relay is programmed for failsafe
mode
using inverting polarity, then its normally closed
contacts will be open if either the meter looses power or a
device fault occurs.
Meter Security
The EM920 provides 3-level password security for protecting
meter setups and accumulated data from unauthorized
changes. Meter readings are not software protected.
Access to particular setup and control items is granted
depending on the security level of the password you entered.
The passwords can be 1 to 8 digits long.
The EM920 is also provided with the security jumper located
on the main CPU board under the meter cover. Removing the
security jumper grants a full access to the meter settings and