As with all mechanical and electrical components, maintaining the products optimum performance throughout its service life is strongly reliant on the implementation of a scheduled maintenance and cleaning program.
HID lighting equipment is no different to this rule; hence the following guidelines serve to provide the user of Pierlite Australia HID lighting systems a professional service schedule for typical Metal Halide and High pressure Sodium lamp wattages of 150watt to 1000watt, E40/E39, reactor ignitor systems.
Maintenance guidelines:
The operation of HID lamps in particular Metal Halide and High Pressure Sodium types consists of four (4) key electrical components namely; a ballast which acts as a current limiting device, an ignitor which provides a high voltage spike to the lamp upon start up, a capacitor providing more efficient usage of power and a lamp which provides the lighting source.
Ballast:
The ballast is the only component in the system that does not require periodic maintenance; providing the ballast has been selected and matched with the approved control gear by the component manufacturer. However, it is important to note that when system components are replaced, eg: a capacitor, the component is replaced with an equivalent rated item and at the time of the maintenance, it is recommended to check the electrical parameters of the ballast to ensure it is operating within the design limits.
The ignitor:
The ignitor provides the necessary (high) starting voltage to activate (ignite) the lamp. The voltage necessary for lamp activation is higher than the available mains voltage; with typical voltage pulses ranging from 1KV to 5 KV depending on the type of lamp.
Currently on the market there are three (3) key styles of ignitors namely: standard, multi-pulse and timed, all of which deliver different system performances.
It is important to consult with your lighting supplier to identify what ignitor system is best suited for your installation requirements eg: generally lower cost (budget) HID luminaires are not fitted with timed ignitors; hence when the lamp fails, the standard ignitor system will continue to attempt to activate the failed lamp and if maintenance programs do not provide for a prompt repair or isolation of the equipment, possible system damage can occur.
So when do i change an ignitor?
Lamp maintenance is critical to ignitor life, the quickest way to reduce the ignitor service life is to have it continuously pulse a failed lamp; this is not recommended as this condition will over heat the ignitor system and lead to premature failure of the component.
As a guide when a failed lamp is changed and the new lamp ignites immediately then the ignitor has not suffered any long term effects; however if the new lamp fails to ignite, then the ignitor will also need replacing.
Under normal operation an ignitor service life will survive four (4) to five (5) lamp changes, if a lamp displays signs of end of life as listed in the Lamp section below and is replaced immediately; ignitor life will not be adversely affected
However, as the ignitor component is a relatively low cost item (compared to accessing the product), it is advisable to consider changing the ignitor during every forth (4th) lamp change.
The capacitor:
Capacitors have a typical service life expectation of 50,000 hours based upon standard operating conditions; however as with all electrical components this performance can be rapidly reduced if the product and components are subject adverse environmental conditions such as:
- Excessive and rapid voltage fluctuations; Excessive condensation for products not designed to accommodate water ingress; High and continued humidity levels in excessive of IEC 60068-2-3;
- Excessive and extended thermal ambient temperatures for products not designed to accommodate such conditions; High mains harmonics.
- As with the selection of ignitor components, it is important to discuss any expected adverse installation parameters with your lighting design to ensure both the correct luminaire and sub-components are selected eg: Pierlite Australia current production guidelines use aluminium cased capacitors rated at 105degree, which are internally fused for added system safety.
So where do i change a capacitor?
Additional to known failed units which should be change immediately, based upon the general lamp life expectation of 13,000 to 20,000 hours (subject to manufactures survival curves). It is recommended to check the system capacitance at each third (3rd) lamp change in accordance with the lamp manufactures guidelines and if the system is found to be out of tolerance, the component should be replaced. To reflect current technology enhancements, it is recommended to replace the component with a fused, high thermal rated, steel cased product.
The lamp:
In general, professional branded HID Metal Halide and High Pressure Sodium lamps have a service life of 13,000 – 20,000 hrs, based upon wattage type, minimum operating intervals and published survival curve parameters.
Adoption of the manufactures operating, installation and maintenance guides are strongly recommended to ensure the optimum performance of the lamp is achieved.
Frequent lamp switch cycles and short operating intervals significantly impact the longevity of a HID lamp and should be avoided.
When a HID lamp has reached its designated end of life the most important task to complete to ensure the system is not unnecessarily damaged, is the prompt replacement of the lamp or isolation of the unit. Typical symptoms of “end of life” conditions are:
- The colour of the lamp changes dramatically.
- There is a significant loss of brightness.
- The lamp no longer ignites or is delayed in striking the lamp.
- The lamp starts to cycle, periodically goes out and then ignites again some time later.
