New Transformers Or Transformers With No Previous Gas Data; Transformers With A Stable Gassing History; Table 2: Recommended Caution/Alarm Settings For Transformers With No Previous Gas Data; Table 3: Recommended Caution/Alarm Settings For Transformers With A Stable Gassing History - Siemens GAS-Guard 8 Operation And Maintenance Manual

GAS-Guard 8 and GAS-Guard 3 Operations and Maintenance Guide

New transformers or transformers with no previous gas data:

Set the GAS-Guard caution level to 50% and the alarm level to 100% of the low-end CAUTION ppm
limits proposed by IEEE PC57.104 Draft 11, published April 21, 2004; except acetylene, as noted below.
Gas
Hydrogen
Methane
Acetylene
Ethylene
Ethane
Carbon Monoxide
Carbon Dioxide
Oxygen

Table 2: Recommended caution/alarm settings for transformers with no previous gas data

Transformers with a stable gassing history:

Use the GAS-Guard to measure the transformer oil for thirty (30) days in order to establish baseline
levels of the eight fault gases. Set the GAS-Guard caution/alarms levels to the measured baseline levels
+ value (PPM) shown below.
Gas
Hydrogen
Methane
Acetylene
Ethylene
Ethane
Carbon Monoxide
Carbon Dioxide
Oxygen

Table 3: Recommended caution/alarm settings for transformers with a stable gassing history

Caution PPM
50
60
2
25
33
175
1750
baseline+10%
Caution PPM
+value (PPM)
+50
+60
+2
+25
+33
+175
+1750
baseline+10%
6 of 18
Alarm PPM
100
120
5
50
65
350
3500
Baseline+20% above initial measured PPM
Alarm PPM
+value (PPM)
+100
+120
+5
+50
+65
+350
+3500
Baseline+20% above initial measured PPM
810-1734-00 Rev A
Notes:
Per Draft 11
Notes: