In the first of a regular feature, energy expert and trainer Vilnis Vesma applies the power of ridicule to motor-driven equipment.
- When a motor fails, have it rewound, as this will reduce its efficiency.
- If you need to replace a motor, use the cheapest and least efficient unit available (preferably oversized). Efficiency standards of new motors are being continuously improved, so you may need to shop on eBay.
- Shift motors slightly on their mounting plates so that any drives and couplings are misaligned.
- Ensure that drive-belts are slack. On multi-belt drives it can help to remove some belts. If possible, use the wrong kind of belt for the pulleys fitted.
- Change pulley ratios to drive fans and pumps at higher speed: on centrifugal fans and pumps, a 20% speed increase adds over 70% to the load.
- Neglect lubrication of bearings and gearboxes.
- Allow equipment to run continuously, whether it is needed or not. This has the added advantage of accelerating wear and tear, and reducing your power factor.
- When the driven equipment is decommissioned, at least leave its motor behind, energised and running.
- In dirty environments, do not clean any debris off motor cooling air inlets. The extra resistance to air flow will increase mechanical losses in the motor and, as a bonus, accelerate its failure by causing it to overheat.
- In situations where the mechanical output of a fixed-speed motor is controlled and regulated, run the motor below its rated voltage in order to increase the motor current and associated copper losses.
Vilnis Vesma provides training in energy management, including the internationally-recognised Certified Energy Manager (CEM) and various short courses, details of which are at www.VESMA.COM/training
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