Sodium gas discharge lamp (HSD): connection via choke and IZU

Features of installation and operation

The most common ballast devices are ballast inductive chokes, which limit and stabilize the current.
The connection diagram for sodium lamps involves supplying supply voltage to the terminals of the lamp. If you connect the NL yourself, it is recommended to use a wire connecting the ballast to the sodium lamp, no more than 1 m long. The use of cotton gloves is also recommended.

When used for artificial lighting of plants, NLs are located no closer than 50 cm from them. Power can be from 75 to 400 W. However, in the case of a power of 400 W, the distance to the plants should be increased to 1.8 - 2 m

Compliance with these conditions is important in order not to damage the plants

A sodium lamp (usually an outdoor one) must be reinforced with a protective glass bulb to avoid damage due to differences in the internal temperature of the bulb and the external environment.

The quality of NL light also depends on their timely cleaning from dust and dirt. To do this, you can use a cloth moistened with alcohol.

Disposal of NL by special institutions is mandatory in order to avoid environmental pollution with mercury vapor (if contained), as well as to prevent an explosion of sodium gas that can occur when it comes into contact with oxygen.

Characteristics and features of using HPS sodium lamps

DNAT consists of the following elements:

Ceramic plug.
A tube that allows light to pass through.
Glass flask, which has high mechanical strength.
Electrode.
A metal rod through which gas is evacuated from the device.
Barium rod.
Base.

The burner is filled with sodium compounds, mercury vapor, and xenon. These gas-discharge substances are necessary to start the lamp.

Reference. There are two types of HPS light sources: low and high pressure. The former emit a muted yellow light, while the latter emit a light yellow light. High pressure devices do not distort color as much as low pressure HPS.

The burner is a cylinder-shaped tube made of aluminum oxide ceramic. Thanks to this material, the flask is resistant to sodium vapor and transmits up to 90% of light. Electrode elements are located on both edges of the tube.

How to make a sodium lamp lamp

Since it is advisable to use HPS products in the household, the use of such light bulbs is relevant for many. But for their operation you will need special lamps. Their cost is high, so it makes sense to build a lighting device with your own hands.

What will you need?

To complete the task you will need:

a metal-coated plate, its dimensions should be 35x40 cm;
aluminum sheet that will be used as a reflective element;
set of self-tapping screws;
hammer;
metal scissors;
pipe with a diameter of 15 cm.

User Anatoly King Crimson spoke in detail about the preparation for the manufacture of a lamp for a HPS light bulb, as well as the creation of such a device.

https://youtube.com/watch?v=mbmFqzkRe_I

Step-by-step instruction

DIY Assembly Guide:

A metal-coated plate is prepared. It should have a mirror surface on the working side, and also be elastic and rigid. If it is not available, it is possible to install a stainless steel plate; this material is used in chimneys. The reflective element is designed to focus the light energy of the device and direct the lighting flux to the desired location. To calculate the dimensions of a reflex device, you can use special computer software that allows you to accurately calculate the efficiency. The plate is bent manually. When carrying out this task, when the central part is bent, you can use a hammer. The rest of the sheet is bent using a previously prepared pipe. To level the surface, you must act carefully. But this can only be done with your hands. At the next stage, the cartridge with the sodium light source is fixed; it can be secured to the back wall. In this example, it is made from the side cover of the PC processor unit. It is recommended to make holes in advance for ventilation of the system. To make a lid, it must be cut out of metal; special scissors are used for this. The socket is fixed to the back surface of the lighting fixture using homemade pins, the diameter of which is 4 mm. These elements are made from hooks purchased in the store. It is desirable that their threaded part be elongated. This will allow you to make several studs. The reflective device is fixed on the rear wall using special aluminum rivets. Their diameter should be 3.2 mm. If you do everything correctly and securely fasten the elements, the structure will ultimately turn out rigid. Then the throttle element, as well as a high-voltage pulse device, is installed in the lighting device

It is important that these components are suitable in size for the lamp body. For more convenient placement, it is possible to remove the board from the case

But the power plug, as well as the switching device with the filter capacitor element, can be left. The throttle is being installed. This example uses a Galad 250W ballast choke element and is optimally suited to the hull width, height and length. A pulse charger is installed next to it. It should have a wiring diagram for the inductor and light bulb, and you need to follow it. At the next stage, wires must be brought out from the housing to the lighting device; their length should be 3 meters. To connect to the socket, only heat-resistant cables must be used. Their insulation should be made of fiberglass. Then the assembled lighting device is configured; this must be done before using it. The lamp is activated; this must be done in a dark room. You must wait until the sodium light source is completely heated. It is necessary to visually assess the quality of the lighting flux, which is reflected by the reflector device. If necessary, this element is bent, but this should be done before it gets hot.

The reflector adjustment procedure must be performed carefully so as not to catch the light source itself. Otherwise, not only the light bulb may be damaged, but it may also explode. To optimize the luminous flux, you can slightly bend the edges of the so-called parabola on the lamp.

User Dmitriy Rostkov spoke in detail about the creation of a reflective device for a HPS light bulb.

Luminous flux and other basic technical characteristics

The abbreviation DNaT 400 stands for sodium arc tube lamp with a power of 400 watts. The device has a simple design. The glass outer housing contains a cylindrical aluminum oxide discharge tube. Inside the tube there is a mixture of inert gases: sodium and mercury vapor, as well as xenon. Two electrodes are soldered into the edges of the tube. There is a vacuum inside the glass flask.

The DNAT 400 lamp has the following technical characteristics:

service life 12000-25000 hours;
Efficiency 30%;
operating temperature from -30С to +40С;
light output 130 lm/W;
power 400 W;
switching time 6-10 minutes;
voltage 220 V +/- 5%;
shape – tubular;
luminous flux 47000 lm;
color temperature 2000 K;
color rendering 20-30 Ra;
pulsation coefficient up to 70%;
base type E40;
length 278 mm;
diameter 48 mm.

Parameters such as luminous flux, luminous efficiency and average burning time depend on the power of the device. HPS bulbs come in 70, 100, 250 and 400 W ratings. HPS lamps are inferior in their characteristics to their LED counterparts, but they are used more often due to their lower cost.

Important! Efficiency directly depends on the ambient temperature. With negative values, the lamps function worse.

There are other types of sodium lamps:

DNaS - arc sodium in a light-scattering bulb, used as a replacement for mercury gas-discharge lamps;
DNaMT – arc sodium matted;
DNaZ – arc sodium mirror.

Since sodium lamps contain harmful substances, they are disposed of in a special way.

Disposal

Sodium, by its nature, is a volatile substance and, in contact with air, can ignite rapidly. For this reason, sodium light sources should not be disposed of as regular waste. Like any energy-saving lamp that contains mercury, they also need to be disposed of in special containers

If you cannot dispose of HPS sodium lamps yourself while observing safety precautions, you should call a special service

Gas-discharge arc sodium lamp DNaT is used to illuminate large areas, city streets, and greenhouses.

Do not confuse low and high pressure sodium lamps. They have different designs and operating principles.

The emission spectrum of both is dominated by orange light. For low-pressure products, the radiation is almost monochrome; they shine with a bright golden light.

If they are used for lighting in rooms, the colors will be practically indistinguishable.

In high-pressure lamps the spectrum is more diverse.

In those models that are used in greenhouses for growing plants, a little blue light is specially added to the light spectrum.

The kit for connecting a high-pressure lamp includes several components, without which you simply cannot start it. That is, simply by applying 220 volts to it, it will not light up.

To do this, you need a special device - a choke or ballast, which in turn is connected according to a certain circuit.

This diagram is often depicted directly on the body.

Here is a more detailed drawing of it.

Painted on it:

the inductor itself (ballast), to which the phase is supplied

then this phase is supplied to the pulse ignition device - IZU

Through it you can connect instances of different power, from 70 to 400W.

The IZU creates a starting impulse for the breakdown of the burner contents in the flask and the formation of an arc. The voltage reaches several thousand volts!

And the burner itself heats up to 1300 degrees during operation.

Only after the IZU is the gas-discharge lamp itself connected.

The same connection diagram can be depicted on the walls of the ignition device.

In addition, it is recommended to use a capacitor in the connection kit. Although it is not present in all schemes.

Why is it needed? As is known, circuits using power chokes consume both active and reactive power. From the second, you will not get any beneficial effect.

This will not make the lamp shine brighter, but the losses will increase. It is in order to remove this reactive component that a phase-compensating capacitor is used.

A visual comparison of the current consumption of a HPS lamp with and without a capacitor:

As you can see, more than double the difference. In the first case, the compensated current (active) is shown, and in the second case, the full current (without a capacitor in the circuit).

Some people think that by doing so they also reduce energy consumption, but this is not entirely true.

Your meter is not designed to count reactive or apparent energy, and the actual cost savings can be a maximum of 3-4%.

But you will eliminate unnecessary losses due to heating of wires and iron.

Here is a compact shield assembled with your own hands, according to the connection diagram.

You can, of course, assemble all this in the overall body of the lamp, if the dimensions allow.

It is very important, before assembling such a circuit yourself and using any components, using a conventional multimeter in the maximum resistance measurement mode, check the insulation of the inductor and capacitor. Is there a hole in the body? Is there a hole in the body?

Is there a hole in the body?

To supply and disconnect 220V power, use a two-pole input circuit breaker.

For one lamp with a power of up to 400W, a machine with a nominal value of 5-6A is quite suitable. In addition to on-off switching operations, it will also play the role of a protective device.

A circuit breaker is mounted at the very beginning of the circuit. Do not forget to also ground the entire panel body.

Two neutral wires come out of the machine. According to the diagram, one of them is connected directly to the lamp, and the second one is connected to the corresponding terminal labeled “N” on the starter.

Otherwise, you can accidentally burn the product if during operation the neutral wire after the ballast choke accidentally shorts out.

And connect the wire from the output contact to terminal “B” (Balast) of the ballast.

After that, connect the middle terminal Lp (Lampa) to the light bulb socket.

Please note that there are two-pin and three-pin IZUs. The first ones are connected in parallel with the lamp itself.

Areas of application

Sodium lamps are used when economic considerations are more important than color rendering. They are not suitable for residential premises, public buildings and production workshops. In addition to poor color rendering, the lamp is dangerous if it malfunctions.

Can be used for seedling growth

DNAT is used to organize street or greenhouse lighting, illumination of architectural monuments and buildings. They are especially common in large cities. They can be recognized by their yellowish-golden hue. The most common elements are 250 and 400 W.

Relatively recently, low-power sodium lamps with a color rendering index of 80 appeared on the market. This indicator is significantly higher than that of other similar models. Therefore, such lamps are effective for lighting decoration in public places.

Sodium light sources are used in the final stages of seedling growth in greenhouses, where shades of blue are often present. Radiation of a significant proportion of the ultraviolet spectrum promotes plant growth. It is important to handle the elements with care, because... destruction of the flask can ruin the entire crop and spoil the soil.

Designers often use sodium elements to imitate fire or the light of the sun.

Low pressure sodium lamps

Low pressure lamps are extremely efficient. The wavelengths indicated above become dominant, but are far from the only ones in the glow spectrum. For low-pressure lamps, most of the lines lie in the area of sensitivity of the eye. This means the light is as bright as possible. In other words, low pressure lamps have an attractive efficiency.

In laboratory models, the efficiency reaches 50-60%. As a result, the luminous efficiency rises to 400 lm/W (the theoretical limit for the current level of technology is 500 lm/W).

We invite you to familiarize yourself with Lamps for plants characteristics

In practice, sacrifices have to be made (Philips bulbs are still good and achieve a luminous efficiency of 133-178 lm/W). The temperature of the flask rises to the required 270-300 degrees Celsius due to special measures for thermal insulation (exceeding the radius of the flask over the maximum effective one) and a slight increase in the operating current to the optimum.

Thermal insulation is sometimes supplemented with other measures. A reflective shirt made of semiconductor materials allows useful yellow radiation to pass out, but reflects infrared radiation inward. The temperature inside rises further. But the design of a sodium lamp is more complicated.

Low pressure lamp

In addition to sodium, mercury vapor and xenon vapor, which reduces the ignition voltage (up to 2-4 kV), are added to the gas mixture. The pressure in the flask ranges from 4 to 14 kPa. It is easy to notice that, according to the general classification of discharge lamps, the indicated range refers to low pressure. For sodium lamps above 14 kPa, the indicated parameter does not rise. The range of 4 – 14 kPa is classified as high pressure.

The maximum efficiency lies around 10 kPa. The partial pressure of sodium vapor is a tenth or twentieth of the total. The rest comes from mercury and xenon. The pressure of the latter (cold) is 2.6 kPa. If a mixture of neon and argon is used to reduce the ignition voltage, the luminous efficiency of a sodium lamp is reduced by a quarter.

Aluminum ceramics is used as the flask material. Ordinary silicate glass is unsuitable; sodium vapor, under the influence of considerable temperature, then enters into a chemical reaction. The compounds formed are stable, and the flask noticeably turns black within a few minutes after the product starts working. The changes are irreversible; under the influence of strong pressure there is a possibility of complete destruction of the glass.

Polycrystalline ceramics and tubular single crystal with wall thicknesses from 0.5 to 1 mm are equally resistant to aggressive environments up to a temperature of 1600 K, with some margin relative to the optimal point. Ceramics exhibit decent transmittance in the visible range, accounting for 30% of the energy consumed by a sodium lamp.

Extreme temperatures require special bushing designs. Made from niobium with a small (1%) zirconium impurity, they are sealed at the entrance to the flask with a special glass cement (capable of withstanding these aggressive conditions). Such a sophisticated alloy in composition was chosen for a reason. The designers have found a material whose thermal expansion coefficient is close to ceramics.

High-pressure sodium lamps are characterized by inertia. When first switched on, the light is yellow and monochromatic. Gradually, the product reaches a mode with a simultaneous expansion of the emitted spectrum. To re-ignite the arc, the gas cools down, taking 2-3 minutes. In order not to exceed operating temperatures, it is necessary to exclude the reflection of radiation onto the flask. Otherwise, the sodium lamp fails due to overheating.

Pros and cons of HPS lamps

Such sodium lamps have several main advantages:

The efficiency factor is very high.
The luminous flux from such a lighting device is quite stable.
The power of this flow is high and amounts to about 150 lumens/watt.
The durability is one and a half times longer than that of other similar lamps.
The color temperature is optimal, the glow has a pleasant golden hue.
Works great even in fog or snow.

Appearance of the HPS lamp

Almost ideal as a phytolamp, since the radiation from HPS actively helps plant growth.
These lighting devices perform well at temperatures ranging from -60 to +40 degrees Celsius.

But, of course, not a single device is without its drawbacks - there are no ideal products. There are 5 main disadvantages:

These lamps are extremely explosive.
There are heavy metals inside.
It takes a long time to ignite (sometimes up to 10 minutes).
When used as a phytolamp, it is not suitable for growing radishes, onions and lettuce, since they are non-flowering.
If it is necessary to connect HPS of higher power (for example, HPS 250 or HPS 400), additional cooling of the lighting device is necessary.

Ballast

Essentially, this is a combination of two main devices - ballast (throttle) and IZU. Without a doubt, electronic ballasts are the best of their kind, unlike inductive devices. However, they are inferior in terms of cost - they are quite high. For this reason, ballast inductive chokes are much more widespread. In some lamps they are already included in the device. That is, it remains to apply voltage to the terminals.

Currently, double-winding chokes are already outdated and in this regard, it is worth paying attention to single-winding types. In this case, the ballast must be designed specifically for light sources of the HPS type and have the same power as the light sources themselves

In this case, the original (that is, “original”) ballast must be present in the connection diagram of the HPS lamp through the choke. Otherwise, no one can guarantee full operation, including their service life. Or the light output of the lamps may decrease significantly.

Other situations cannot be ruled out either. For example, the “blinking” effect is when the lamp can go out immediately after heating, and after it cools down the whole process is repeated again.

Connection diagram for a HPS lamp with a two-pin IZU

The connection diagram for the HPS lamp, which is shown in the first figure, is designed to contain a compensating capacitor connected in parallel to the power source. This is a dry type C capacitor, which is designed to compensate for the inductive component of the system - reducing reactive power consumption, reducing overall electricity consumption, as well as extending the service life of the finished product.

For example, to connect a HPS lamp with a power of 250 W (3A), a compensating capacitor capacity is provided (operating voltage indicators are 250V) of only 35 μF. This capacitance can be formed using several capacitors connected in parallel.

Sometimes capacitance indicators may be provided by the manufacturer, but an extremely large increase can lead to resonance in the circuit, and, consequently, to ineffective operation of the finished product.

If the HPS connection occurs independently, the permissible value of the location of the IZU should be taken into account. It should be located as close as possible to the base of the product, while the length of the connecting wires in this area should be minimal (the maximum permissible value is 1.5 m).

To ensure a high-quality and safe connection, high-voltage ignition wires for special purposes are used.

Connection diagram and what is needed to start DNAT