61
UMG 509-PRO
www.janitza.com
11.3.2
Transients
The device:
·Monitors the voltage measurement inputs for
transients.
·Detects transients that are longer than 50 µs.
·Can detect transients according to two indepen-
dent criteria.
·Can receive different monitoring settings for
each phase.
The addition of an "(LN)" or "(LL)" indicates the
dependence of the calculated voltage values for
the transient setting.
When a transient is detected:
·The waveform is stored in a transient recording.
·The limit value, both in automatic and manual
mode, is automatically increased by 20 V for the
next 10 minutes.
·For a period of 60 seconds each further transient
is recorded with 512 points.
Fig. Example "Relevant voltage" U
LL
Fig. Setting MAIN "Transients" U
LL
You can display recorded transients using the
GridVis® event browser.
The following modes are available for recording
transients:
·
absolute
·
delta
Mode (absolute)
If a sample value exceeds the set limit value, a
transient is detected:
·
off
- The transient monitoring is switched off
·
automatically
- Factory default. The limit value
is calculated automatically and is 150% of the
momentary 200 ms RMS value.
·
manually
- The transient monitoring uses the
configurable limit values under "Peak".
Fig. Configuring the transient recording mode
INFORMATION
Automatic determination of the mains frequen-
cy requires that a voltage L1-N of greater than
10 Vrms be present at voltage measurement input
V1.
