Overview

The special feature of superimposed-pulse ignitors is that the ignition voltage is generated without placing a high-voltage load on the choke. Superimposed-pulse technology leads to a reproducible ignition response which does not depend on the control gear used and is unaffected by voltage fluctuations.

Pulse ignitors are operated with chokes tailored specifically for them. Integrated shutdown of defective lamps reduces the load on the chokes to a minimum. Restart attempts in pulse-pause mode reduce the load on the chokes still further.

Tridonic ignitors ensure lamps start reliably even if the mains voltage is as low as 198 V (switch-on voltage). The ignitor is switched-off as soon as the lamp starts to prevent damage to the lamp. Because of the high-quality narrow-tolerance components the switch-off voltage reaches the high value of 185 V.

The increase in temperature in the ignitor determines its area of application and is therefore an important criterion. Tridonic ignitors are characterised by minimal self-heating, which in turn gives luminaire designers extra creative freedom.
 

Superimposed-pulse ignitors

In ignitors that operate on the superimposed principle the ignition voltage is generated by an integrated pulse transformer.

This transforms the mains voltage to the ignition voltage of up to 5 kV required by the lamp.

A cleverly designed circuit is used to control the ignition process. This means that superimposedpulse ignitors from Tridonic have high system reliability and reproducibility of the ignition pulses, which are largely unaffected by fluctuations in the mains voltage.
 

Superimposed-pulse ignitors with timers

Sodium lamps and metal halide lamps connected to conventional ignitors begin to flicker at the end of their lives. This is avoided by ZRM ES/CT superimposed-pulse ignitors with integrated digital timers and pulse-pause ignition.

The ZRM ES/CT ignitor does not generate ignition pulses constantly but in a patented two-part rhythm, creating the optimum conditions for igniting the lamps.

The lamp has time to cool down in the pauses after ignition. This leads to much faster restarts for hot lamps. Thanks to pulse-pause ignition the system downtime is reduced considerably.

The μ-chip of the integrated timer in the superimposed-pulse ignitor digitally controls the logic for ignition and automatic shutdown. An automatic reset function is also integrated. This reset function is needed for lighting systems that operate 24 hours a day (tunnels, factories).
 

Ignitor systems using pulse technology

In pulse ignitors the high-voltage pulse is produced in conjunction with the choke. The ignitor uses a separate tap on the choke, specially developed for pulse technology and designed for high ignition voltages.

As the high-voltage pulse is generated in the choke for the ignition process it is possible to achieve very high ignition energy.

The digital ZRM powerPULSE from Tridonic compensates for the dependence of the output voltage on the mains voltage by using a microprocessor in the ignitor to control the production of the ignition pulse. This ensures that the choke and luminaire wiring are not overloaded if there is a mains overvoltage. It also ensures that in the event of a mains undervoltage or if there are extremely long connecting cables the required ignition energy is constantly available.

The benefits of pulse/pause technology are evident in the ZRM powerPULSE ignitor as this ignitor reduces the restart time and EMC interference in the ignition phase.

Another feature is the integrated digital three-start counter. This stops the ignition process after three unsuccessful lamp starts to suppress lamp cycling when the lamp comes to the end of its life and avoid overloading the control gear with the high-voltage pulses.
 

Power changeover switches

Power changeover switches are used predominantly in street lighting to reduce the lighting level by as much as 50 % at off-peak times and therefore also reduce energy costs by a significant amount.

Tridonic offers power changeover switches for lighting systems with or without a control line. If a control line is present then power changeover switch ZRM U6L is used. This is also available with an integrated timer.

The timer ensures that the lamp is operated for a defined period of time at full output during the start phase. This in turn ensures that the life of the lamp is not reduced unnecessarily.

If there is no control line then power changeover switch ZRM U6M is used. The on and off times can be programmed centrally at any time even after installation has been completed. ZRM U6M is suitable for magnetic chokes with power tapping and also for PCIS outdoor DIM electronic ballasts.
 

Supplementary impedances

Supplementary impedances are used to upgrade existing luminaires with inefficient mercury vapour lamps to energy-efficient sodium vapour lamps.

Only one additional component is needed for the upgrade – the supplementary impedance with integrated digital ignitor. Because the existing choke is retained the upgrade is simple and cost-effective.

ZRM A001 and ZRM B001 from Tridonic have enhanced insulation and an integrated cutout in the event of a lamp fault. They are therefore approved for protection class 2 applications. The supplementary impedances are available in two casing designs and are equipped with 500 mm long connectionwires.
 

Ignition time bridging

Since high-intensity lamps require a certain starting time to reach their full output an additional lamp can be used to bridge this starting phase. The additional lamp provides sufficient light until the high-intensity lamp has completed the starting phase. The additional lamp is controlled by LRM 500. As soon as the high-intensity lamp produces enough light (about 90 % of full output) the additional lamp is switched-off.
 

Standards and approval marks

Ignitors and power switches from Tridonic are ENEC certified, carry the CE mark and meet all the relevant European as well as international standards relating to safety, operation and electromagnetic compatibility (EMC).