The light ballast delivers the right commencing voltage, working voltage and current around the lamp to initiate and sustain the arc. HID lamps have a damaging resistance characteristic, which prospects to them to draw an rising amount of existing, hence need a present limiting gadget. The ballast delivers these functions. There are various exclusive ballast sorts employed for for HID lighting. Fundamentally, you’ll find two main distinctions among ballasts: “lag circuit” and “lead circuit” ballasts. The existing in lag form ballasts is managed by an inductive resistance in series with the lamp, whereas in lead style ballasts it existing management is presented by every single inductive and capacitive resistances in series together with the lamp.
Now these, lag and lead kind circuits may possibly be generated inside a number of various approaches, every single with thier personalized qualities and gains and disadvantages.The simplest lag circuit, is really a single core and coil positioned in series with all the lamp – that is normally known as the Normal Electrical power Element ballast. Note, there may be definitely NO capacitor utilised on this circuit. The trouble with this unique number of circiut may be the power component is about 50% lagging, therefore the title normal or decreased energy element. This type of circuit tends to get delicate to fluctuations in line voltage, and is not proposed for fluctuations over 5%. The line current at commencing issues might be about 50% higher than ordinary operating current.
To enhance the electrical energy aspect over the circuit, a capacitor is linked across the input lines. The capacitor’s major perform proper here will probably be to appropriate the energy factor, increases it to all-around 90%, and minimizes the starting current draw, hence enabling more ballasts to be run in excess of the precise exact same circuit. Note the capacitor won’t have an impact on the lamp circuit.
CWA – Frequent Wattage Autotransformer is surely an extra circiut utilized in ballasts. This can be a lead variety circuit and it can be applied in many modern day mercury lighting applications. This ballast design involves a significant reactance autotransformer and capacitor in series together with the lamp. In contrast to the 2 circuits outlined over specifically exactly where the capacitor only serves to supply a correction in the direction of the electrical electrical power facet, the capacitor ideal here types a substantial ballasting function, and lets the lamp to operate with much better stability beneath fluctuating voltage scenarios. It actually is among the most efficient circuit, and consequently most well-known.
The circuits stated over are employed frequently with mercury vapor lamps. The James lamp is intended getting a substitute for mercury vapor lamps, and hence calls for any ballast ideal for mercury vapor lamps. The ANSI designation of mercury vapor ballasts for 250W lamps is H-37 and for 400W is H-33. So in idea, any ballast with all the H-33 designation have to have to drive a 400W James lamp.MH ballasts, carry out an incredible deal this kind of since the CWA ballasts for mercury lamps, and also have the ANSI designation M-58 for 250W and M-59 for 400W. Generally, you can find the ballasts used for aquarium lighting have dual rating M-58 & H-37, M59 & H-33. Consequently these ballasts might be employed for just about every MH and MV lamps. But remember that these are CWA ballasts.
Now the James lamps, in the pamphlet that comes together with the lamps, says “250W Reactor or Autotransformer type Mercury ballast without peaking capacitor. Do not use on Regulator (CW and CWA)” They recommend a Large Energy Component ballast.