An Uninterruptible Power Supply (UPS) provides emergency power when the power source or mains power fails. A UPS differs from an emergency power system or standby generator in that it provides near instantaneous protection from power interruptions by supplying energy stored in batteries, supercapacitors or flywheels. The on-battery run time of most UPS is generally short (minutes rather than hours) but is sufficient to start a standby power source or properly shut down the equipment.

A UPS is designed to protect your vulnerable, and often expensive hardware from physical or memory-based damage if they’re suddenly disconnected from mains power. UPS’ are typically used to protect hardware such as computers, data centres, telecommunication equipment or other essential electrical equipment such as emergency lighting or alarm systems.

While a UPS’ main role is to provide short-term power when there is a power failure, most UPS units can also, in varying degrees, correct common utility power problems such as voltage spikes, sustained over voltage or momentary or sustained reduction in input voltage

What size UPS do I need?

Any UPS you install must be large enough to support all the equipment plugged into it. This means you need to calculate the load required. The load is the total amount of power drawn in watts of all the devices that are or will be plugged into the UPS. Once you know the load, you can select a UPS with the right capacity for your needs. The capacity is how much power a UPS can provide (measured in watts) if needed.

The runtime required in the event of power outage will also determine the size UPS you need. Runtime is the number of minutes a UPS can support the attached devices during a blackout.

The minimum runtime should be the time needed to complete proper equipment shutdown.

The smaller the wattage load connected to the UPS the longer the batteries will last. To determine the runtime you need, start with the number of minutes required to completely shut down the connected devices. If a long runtime is required you can upsize your UPS so the connected load is a smaller percentage of the capacity or, with some UPS units, you have the ability to add additional battery modules to extend runtime.

Different types of UPS

• A Standby UPS is an offline unit that can detect a mains power failure and switch to battery power automatically. In normal operation the load is fed directly by mains power.
  
• A Line-interactive UPS conditions the mains power by regulating input voltage up or down in a buck-boost transfer, before allowing it to pass through to your protected equipment. In the event of a mains power failure, battery power is provided automatically.
  
• An on-line UPS converts power tiwce. First an input rectifier converts AC power into DC and feeds it to an output inverter. The output inverter then converts the power back to AC before sending it on to the protected equipment. This double conversion process insulates critical loads from dirty mains power completely to ensure that the connect equipment receives only clean reliable electricity.
  

UPS Maintenance

UPS’ should be regularly maintained to ensure that they are ready to function when you need them. Investing in a planned maintenance programme for your UPS can improve both reliability and the overall lifespan of your system. A well maintained and regularly serviced UPS needs less power to run, as well as being far less likely to fail and cause critical downtimes.

Preventative Maintenance Checks for your UPS:

• Internal and external checks
• Calibration of all metering and protective features if required
• Functional testing of all transfer conditions
• Inspection of on-line performance of equipment with load
• Visual check of batteries and battery environment
• Testing of battery voltage.

The EAS are highly skilled in sizing, installing and maintaining UPS’. If you would like to discuss protecting your essential equipment with a UPS get in touch with the EAS team today on 07 834 0505 or [email protected].

All electrical products generate heat and therefore have the potential to be a fire risk if not properly maintained. Worksafe have highlighted in this months’ newsletter in conjunction with the Lighting Council the need to ensure that Fluorescent and High Intensity Discharge (HID) light fittings are being regularly maintained due to the number of fire related incidents they have been involved in recently.

Most fluorescent and HID lights supplied and installed in New Zealand over the past 30 years contain replaceable power factor correction capacitors. Regular maintenance including checking and replacing aged components is essential to ensure they operate safely and efficiently. HID type lights include metal halide, high pressure sodium and mercury vapour technologies.

Proper maintenance of any lighting system is essential to maintain levels of illumination necessary for productivity, merchandising, visual comfort, safety, and security. However, Worksafe’s key concern in highlighting the need for this essential maintenance is the increased risk of failure and fire these lights pose if not regularly maintained.

If an individual component fails and remains in the lighting system, costly damage to other components can result. Major repairs can often be avoided by simple maintenance procedures and timely attention to small problems, such as replacing burned-out lamps. Preventing a problem from occurring is more desirable and economical than fixing it later. A scheduled program of preventive maintenance can save money while maintaining productivity and safety.

EAS recommends the following servicing of fluorescent and HID lights to ensure best performance and safety:

• Lights should be serviced at least every three years and whenever fluorescent tubes and HID lamps are replaced.
• HID lighting fixtures should periodically be inspected for lamps cycling on and off, heavy
  lamp discoloration, dim lamps, slow-starting lamps, inoperative lamps and dust and dirt.
• When any capacitors, ballasts, lamp holders or starters show signs of ageing. These should be replaced immediately.
• Capacitors have a life span of five to ten year. These must be replaced within the 10 year period.
• A maintenance record of the components, the dates they’ve been checked and the dates that any components have been replaced should be
  kept.  EAS can assist you with establishing and maintaining a maintenance record for
  your lighting.
• Any lights that are subject to high ambient or external heat will require more regular checks and maintenance. EAS recommends a six monthly check for these lights.

EAS can coordinate the whole process of maintaining and installing your fluorescent and HID lighting. Ensure your lights are safe by getting in touch with the EAS team for a maintenance check today on 07 834 0505 or [email protected].

One of the tricky things about electrical systems is that you often can’t see faults without taking things apart.

Thermal imaging is a non-intrusive, non-contact method of detecting electrical faults that are hidden to the naked eye. Thermal imaging can be used as a fault-finding measure or as preventative maintenance as it can indicate faults that you may be completely unaware of because electrical systems are largely hidden from view. Heat is often an early symptom of equipment damage or malfunction, making it important to monitor in preventative maintenance programmes.

Thermal imaging can reduce the likelihood of unplanned downtime due to equipment failure, reducing the costs of reactive maintenance and unplanned downtime. It can also help extend the lifespan of your assets.

Thermal imaging detects infrared radiation from an object. Based on the amount of energy detected it works out the temperature. This is translated into an electronic picture or thermograph which will highlight a warm object against the cooler area around it.

Thermal images can be greyscale with cold objects depicted as black, warmer ones as tones of grey and hot ones as white or the thermal camera can add colour with reds, yellows and oranges showing the warmer objects and greens, blues and purples and blacks showing the cooler ones.

There are 3 typical methods of thermal inspection:

• Baseline thermography Equipment is scanned when it is first commissioned or later in the lifecycle when it is operating as it should. This is then used as a point of reference for future inspections.

• Thermal trending Once a baseline has been set, thermal trending inspections can be undertaken to compare how temperature is distributed in the same components over time. This can help detect declining performance so you can schedule downtime maintenance before you have an equipment failure.

• Comparative thermography
  Similar components are scanned with a thermal camera under similar conditions and the results are compared. This method relies on the idea that you can expect similar or identical components under similar loads to have similar temperature profiles. Once you have three or more components its relatively easy to pick up an anomaly.

What can you check with thermal imaging

• Electrical Panels:
  Thermal images are an easy way to identify apparent temperature differences in industrial three-phase electrical circuits. By inspecting the thermal gradients of all three phases side by side, technicians can quickly spot performance anomalies on individual legs due to unbalance or overloading. Thermal images should be taken of all electrical panels and other high load connection points such as drives, disconnects, controls etc. Ideally electrical devices should be checked when they’re fully warmed up and at steady state conditions with at least 40% of a typical load. That way measures can be properly evaluated and compared to normal operating conditions.What to look for:
  Equal load should equate to equal temperatures. In an unbalanced situation, the more heavily loaded phases will appear warmer than the others due to the heat generated by resistance.

• Roller, chain and belt conveyors
  Thermal imaging is especially useful for monitoring low-speed mechanical equipment like conveyors. Overheating signals the impending failure of many different electrical and mechanical conveyor components, from motors, gearboxes and drive to bearings, shafts and belts.What to look for:
  Any hot spots, paying special attention to differences in temperature of similar components operating under similar conditions. For some conveyor components such as drives, thermal imaging complements other condition monitoring technologies such as oil analysis, vibration monitoring and ultrasound.

• Motors & Drives:
  Ideally motors should be checked when they are running under normal operating conditions. Thermal cameras can capture temperatures at thousands of points at once, for all of the critical components – the motor, shaft coupling, motor and shaft bearings and the gearbox.What to look for:
  All motors should list the normal operating temperature on the nameplate. While the thermal camera can’t see inside the motor the exterior surface temperature is an indicator of the internal temperature. As the motor gets hotter inside it also gets hotter outside. This will help identify where further investigation is required into the cause of the overheating such as inadequate airflow, impending bearing failure, shaft coupling problems and insulation degradation in the rotor or stator of the motor.

• Steam systems:
  Thermal images of steam systems compare the temperatures of system components which indicates how effectively and efficiently they are operating. Using a combination of ultrasound and thermal inspections significantly increases the detection rate of problems in steam systems.What to look for:
  Steam traps are valves designed to remove condensate as well as air from the system. During inspections, both thermal and ultrasonic testing should be used to identify failed steam traps and whether they have failed open or close. In general, if a thermal image shows a high inlet temperature and low outlet temperature (<100°C) that indicates that the trap is functioning correctly. If the inlet temperature is significantly less than the system temperature, steam is not getting to the trap.

The EAS are highly skilled in carrying out thermal imaging. To check the condition of your vital equipment get in touch with the EAS team today on 07 834 0505 or [email protected].

The Answer is 042

Didn’t get it right? Check out these instructions for how to solve it.

The answer is 23

pair of shoes = 10
Boy = 5
Double burger = 4
One shoe = 5
Boy with 2 burgers = 9
One burger = 2

One shoe + (Boy with 2 burgers x one burger)

= 5+9×2

= 5 + 18

= 23