Step 2: Start monitoring
Having got your PEL, decide where to install it – usually this will be in a distribution cabinet – and set it up to monitor the circuits that interest you. Typically, these might be lighting, HVAC and possibly computer systems. Remember that some three-phase PELs, including the PEL103, can be used to monitor three single-phase circuits simultaneously which saves a lot of time. Set your PEL to make recordings over a period; a day is good, but a full week is better, as interesting things often happen at weekends! Later, you may find it useful to record information over even longer periods, which is another good reason for buying your own PEL.
Step 3: What happens out of hours?
When you’ve got the data from your PEL, the first thing to look for is out of hours usage. How much energy is your business continuing to use after the workers have gone home in the evening and over the weekend? You may be in for a shock – British Gas recently surveyed 6,000 SMEs and discovered that 46% of their electrical energy usage occurred outside normal business hours. Some of this usage is necessary, of course, but a lot isn’t and, armed with reliable information from your PEL, you’ll be able to address this issue – the solution is often no more costly or complicated than installing a few time switches.