Generators are usually used where there is likelihood that the load cannot be off for any length of time or in areas where the mains supply is less than reliable. Life critical systems always demand long-term support and large computer or data installations, relating to telecoms, call centres and financial institutions usually have similar needs. Any company that will suffer significantly from long-term power outages would benefit from a generator installation. If being used to support a UPS or rectifier as part of the load, the generator and control system should be carefully selected to avoid compatibility problems.