janitza UMG 509, Operation Manual And Technical Data

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UMG 509
Transients
Transient voltages are fast impulse transient effects
in electrical networks. The time when transient voltages
occur cannot be predicted and they have a limited
duration.
Transient voltages are caused by lightning strikes,
switching operations or by tripped fuses.
• The UMG 509 detects transients that are longer
than 50µs.
• The UMG 509 monitors the voltage measurement
inputs for transients.
• The transient monitoring can be adjusted for each
phase.
• There are two independent criteria by which
transients are detected.
• If a transient has been detected, the wave form will
be saved to a transient record.
• If a transient has been detected, the threshold
value increases by 20V, both in automatic and
in manual mode. This automatic increase of
the threshold value switches off within 10 minutes.
• If a further transient is detected within the next
60 seconds, it will be recorded with 509 points.
• The GridVis event browser can display recorded
transients.