Sparks Electrical News September 2018

CONTRACTORS’ CORNER

16

ON THE GROUND WITH JONAS E MUKUPO

THE IMPORTANCE OF MAINTENANCE

T his month I would like to discuss ‘mainte- nance’. I will venture into the different types of maintenance, and dissect each one. Preventative maintenance It is said that ‘prevention is better than cure’, and the same applies to the maintenance of machinery run- ning production lines, or switchgear that carries the energy to spin the motors that eventually turn the conveyor belts. Preventative maintenance often in- volves using sensors, etc. to determine the condition of in-service equipment so you can predict when maintenance should be performed. In effect, sensors listen, look and smell, and as a plant manager, or any other production member of

staff, you can do the same on your daily plant walks. When you hear or sniff an unfamiliar sound or smell coming from machines, cables or switchgear, you can launch an immediate investigation to identify the anomaly. The necessary measures can then be implemented to avoid breakdowns – which mean down time, which means production losses, which mean profit losses and subsequent repercussions. Scheduled maintenance Scheduled maintenance is planned maintenance; it is time or period based. For example, a factory can choose to have all machinery serviced after a year of continuous running, commonly referred to as the ‘annual shutdown’. In the construction industry this

happens is that a breakdown occurs and, because of the necessary downtime – since nothing can happen on the production line (for example, a transformer blows and the factory cannot operate because of this) – that time is used to carry out maintenance on the idle machinery and/or switchgear. This brings me to what I deal with on daily basis as a contractor specialising in switchgear maintenance; servicing, testing, checks and retrofitting. There is nothing that can be classified as ‘maintenance-free’, as has been the talk in medium voltage circles. Yes, I have heard about ‘30-year service free or no service’ clauses on certain medium voltage products but, personally, I believe that a monthly walkabout into those substations and taking readings helps us to identify the unfamiliar noises and smells I alluded to earlier, and saves huge replacement costs by identifying areas that need attention. Oil level checks on a transformer or gas levels on the gauge of switchgear with SF6 gas, such as most RMU (Ring Main Units), will help save the pennies in financially trying times compared with the cost of replacing a transformer, or switchgear and cables downstream. As a rule of thumb with regards to switchgear, the following applies: one year after installation (new switchgear) carry out a ‘Test and Check’. This is a testing operation of the trip unit to check mechanical operation, status of lubricant on moving parts and main contacts, taking into consideration the environment in which the switchgear operates. After this, a yearly service should be carried out and include cleaning and relubricating mechanical parts, testing the breaker trip unit, and cleaning the ‘truck’ or cradle and relubricating the clusters. Please note that operating environments determine if these periods can be shortened. Do maintenance, save money!

shutdown refers to the period during which the in- dustry closes for the December holidays, but on pro- duction lines, it is a time to stop all the machines and carry out repairs such as changing bearings on mo- tors, changing drive belts, and servicing all switch- gear, be it HV, MV or LV depending on the operation systems. Breakdown or corrective maintenance As the name suggests, breakdown maintenance takes place after a breakdown and in managing for simple breakdown maintenance you ensure you have available spare parts for a quick fix. In more serious breakdowns, and forgive me for calling this ‘opportunistic’ maintenance, what usually

By Jonas E Mukupo IE32127, MJ Total Power Solutions-Electrical & Switchgear Contractors

LIGHTING AFRICA PROJECT LAUNCHES IN TANZANIA

H anergy Thin-Film Power Group has launched the Lighting Africa project at its first stop in Tanzania together with China Foundation for Peace and Development and Tanzania-China Friendship Association by promising to donate the first 100 Humbrellas this October. Lighting Africa is a philanthropic aiming to provide environmental-friendly lighting devices to African children to improve their reading time and help electricity deprived populations in Africa. Humbrella is a new thin-film solar product developed by Hanergy. Weighing only 8.8 kg and at a diameter of 2.7 m, Humbrella is covered with thin-film solar panels, which are available for power generation in sunny or cloudy days. Equippedwith integrated functions of off-gridpow- er supply, electricity storage, night lighting and termi- nal charging, the newly unveiled product is expected to store asmuch as 40 000mAh electricity, ensuring 10-hours of high-quality reading time for children, or charging more than ten 3000 mAh smartphones.

Enquiries: www.hanergy.com

SPARKS ELECTRICAL NEWS

SEPTEMBER 2018