On the packaging of LED lamps can be found a lot of parameters: power, luminous flux, the equivalent power CRI. But one very important parameter manufacturers indicate extremely rare. This type of driver.
By GOST 29322-92 network voltage must be 230 volts, but the same Standard deviation allows mains voltage ± 10%, i.e. permissible voltage of 207 to 253 volts. However, in many areas (especially rural) stress sometimes drops to 180 volts and below.
When undervoltage conventional "bulbs Ilicha" shine much dimmer. The lower threshold of acceptable voltage 207 volt, 60-watt incandescent bulb, calculated on 230 shines as a 40-Watt nominal voltage (ammo1.livejournal.com/671053.html).
Operation of LED lamps at the reduced voltage is dependent on the type of electronic circuits (drivers).
If the lamp is used a simple RC-driver or line driver IC, the lamp behaves in much the same as an incandescent lamp (lights dim at low voltage, and at the races in the voltage of its light "Twitches").
If you use IC-driver, the brightness of the lamps does not change when power supply in a very wide range. In fact, these lamps have a built-in stabilizer.
If you look at all the LED lamps, which I tested in Lamptest.ru project, specifying the type of driver, it appears that 3/4 of all lamps IC-driver, and only a quarter of a linear or RC-driver. If we look only at the filament lamp, the picture changes dramatically: from 321 lamps tested only in 131 (40%) IC-drivers.
Most lamps with linear driver brightness falls to 5% of the nominal voltage sags up to 210-220 V and 10% at a voltage of 200-210V.
Some with IC-lamp driver does not reduce the brightness even when the voltage drops to 50 volts, but most stably operated at a voltage of 150 volts.
That's behaving two filament lamps (left with IC-driver, right - linear) when the voltage is varied from 230 to 160 volts.
I measure the minimum voltage at which the lamp luminous flux decreases by no more than 5% from the nominal. Table Lamptest this voltage results indicated in column "Vmin". If the voltage drops light output begins to fall immediately, I point linear (LIN) driver type (column "drv"), if the luminous flux at reducing the voltage is stable, and then begins to decline, - the type of driver IC1, if voltage reduction lamp turns off, - of IC2 when starts flash - IC3.
Unfortunately, the type of packaging and the lamp driver parameters provided by manufacturers on the site, it is almost impossible to know. Some manufacturers write on the package, "the IC driver." Often write a wide voltage range, such as "170-260V", but this is not always true. On Lamptest many lamps that have shown wide voltage range, but in fact they set line driver and at the lower end of this range they burn "half-heartedly". Note the narrow range of "220-240 V" or simply "230" also does not speak about anything: a plurality of such lamps built on the IC-driver and actually operate at much lower voltages without compromising brightness.
All I can advise to determine the type of driver - watch the results on Lamptest on the lamp or her analogs (same manufacturer, the same type, the same base), if the particular model of the lamp is not tested.
Of course, with the IC-lamp driver better. They do not change the brightness when the voltage drops in the network and their light is not "jerks" when voltage drops. In addition, this driver obviously better protected from any voltage drop and generally more reliable.
I recommend to consider when choosing a LED lamp driver type and possibly to buy a lamp with IC-driver.
© 2019 Alex Nadozhin, creator of the project Lamptest.ru