• The battery operates the charger on a 24 - hour basis .
• The plant operates 24 hours a day [ or ( a ) round the clock] .
• The battery operates the charger on a 24 - hour basis .
• The plant operates 24 hours a day [ or ( a ) round the clock] .
Циммерман М., Веденеева К.. Русско-Английский научно-технический словарь переводчика. Russian-English scientific dictionary for translators. 2012