Downgrade, as electrical units

• Reduce taxes, in Britain
• Lower the grade of
• Lower the value of
• Lower the charges on
• Lower the electrical capacity of
• Lower the assessed electrical capability of
• Lower the capability of

Wiktionary Word definitions in Wiktionary
vb. To lower the rated capability of any rated equipment or material.

WordNet Word definitions in WordNet
v. lower the rated electrical capability of electrical apparatus