janitza UMG 512-Pro, User Manual And Technical Data

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UMG 512-PRO www.janitza.com
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11.3.2 Transients
The device:
·Monitors the measurement inputs for transients.
·Detects transients that are longer than 39 µs.
·Can detect transients according to two indepen-
dent criteria.
·Indicates transients as a function of the set rele-
vant voltage.
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.
·Each further transient is recorded with
512 points for a period of 60 seconds.
You can display recorded transients using the
GridVis® event browser.
The following modes are available for recording
transients:
· Absolute
· Delta
· Envelope
Mode (absolute)
If a sample value exceeds the set limit value, a
transient is detected:
· Off - The transient monitoring is switched off
· Automatic - Factory default. The limit value is
calculated automatically and is 150% of the
current 200 ms RMS value.
· Manual - The transient monitoring uses the con-
figurable limit values under "Peak".
Mode (delta)
If the difference of two adjacent sample points ex-
ceeds the set limit value, a transient is detected:
· Off - The transient monitoring is switched off.
· Automatic - Factory default. The limit value is
calculated automatically and is 0.2175 times the
current 200 ms RMS value.
· Manual - The transient monitoring uses the con-
figurable limit values under "Trns U".
Fig. Example "Relevant voltage" U
LL
Fig. Setting MAIN "Transients" U
LL