2011IEEE C57.12.40-2011 Network@ Three-Phase Transformers@ 2500 kVA and Smaller; High Voltage@ 34 500 GrdY/ 19 920 and Below; Low Voltage@ 600 V and Below; Subway and Vault Types (Liquid Immersed)
2006IEEE C57.12.40-2006 Standard Requirements for Secondary Network Transformers@ Subway and Vault Types (Liquid Immersed)
2000IEEE C57.12.40-2000 Secondary Network Transformers Subway and Vault Types (Liquid Immersed)Requirements (Replaces NEMA C57.12.40-2000)
1990IEEE C57.12.40-1990 SECONDARY NETWORK TRANSFORMERS - SUBWAY AND VAULT TYPES (LIQUID IMMERSED) - REQUIREMENTS (Now Copyrighted by NEMA)
1982IEEE C57.12.40-1982 REQUIREMENTS FOR SECONDARY NETWORK TRANSFORMERS@ SUBWAY AND VAULT TYPES (LIQUID IMMERSED)