Measurements - ABB REU 610 Technical Reference Manual

1MRS755769
5.1.2.
Voltage Relay
Technical Reference Manual
If the synchronization pulse differs more than ±0.05 seconds for second-pulse or ±2
seconds for minute-pulse synchronization from the relay's real-time clock, the
synchronization pulse is rejected.
Time synchronization is always triggered on the rising edge of the digital input
signal. The time is adjusted by accelerating or decelerating the relay's clock. By this
way the clock neither stops nor makes sudden jumps during the time adjustment.
The typical accuracy achievable with time synchronization via a digital input is ±2.5
milliseconds for second-pulse and ±5 milliseconds for minute-pulse
synchronization.
The pulse length of the digital input signal does not affect time
synchronization.
If time synchronization messages are received from a communication
protocol as well, they have to be synchronized within ±0.5 minutes at
minute-pulse or ±0.5 seconds at second-pulse synchronization.
Otherwise the time difference may appear as rounding errors. If it is
possible that the synchronization messages from the communication
protocol are delayed more than 0.5 seconds, minute-pulse
synchronization must be used.
When the minute-pulse synchronization is active and long time format
is sent via a communication protocol, the protocol's second and
millisecond part is ignored. The protocol's minute part is rounded to
the nearest minute. Short time format is ignored altogether.
When the second-pulse synchronization is active and long or short time
format is sent via a communication protocol, the protocol's millisecond
part is ignored. The protocol's second-part is rounded to the nearest
second.

Measurements

The table below presents the measured values which can be accessed through the
HMI.
Table 5.1.2.-1 Measured values
indicator
U
12
U
23
U
31
U
0
U
1s
U
2s
Description
Measured phase-to-phase voltage U
Measured phase-to-phase voltage U
Measured phase-to-phase voltage U
Measured residual voltage U
Positive phase-sequence voltage
Negative phase-sequence voltage
REU 610
12
23
31
0
21