Pd Live Hf Noise Threshold Measurement - GE Kelman DGA 900 Plus Installation & Commissioning Manual

Figure 10-26: Bushing Alarms Configuration
To disable instantaneous Tan δ measurements:
▪
Select BMT > Configuration as shown in Figure 10-27 to verify the 'Exponential
Moving Average Configuration'. Ensure that:
− 'Daily Moving Average Enable' is On
− 'Moving Average Factor Phase Angle' is 10000
Figure 10-27: Exponential Moving Average Configuration

10.4.5 PD Live HF Noise Threshold Measurement

The HF input noise can range over many orders of magnitude depending on the
transformer, so the 'Live HF Noise' is used to estimate the input noise levels and
consequently adjust the input gains.
▪
Select BMT > Configuration and scroll down to the 'Live HF Noise' section as shown
in Figure 10-28.
Figure 10-28: Live HF Noise
If the 'Live HF Noise' value for any channel exceeds 180, scroll further down to the 'HF
Gain Control' section and select High gain for each affected channel as shown in Figure
10-29.
MA-041 – DGA 900 Plus - Installation & Commissioning Manual - Rev 1.1 4-Mar-22 Page 90 of 99