They brought a lamp ( Fig.1), asked to see if anything could be done to make it work. There is only one lamp in the housing, it does not respond to switch switching, and when powered from the mains there is no reaction either. There are no instructions, no diagram... Okay, I'm going online to look for at least some information... Yep, there is a photo and description - this model with thin T5 fluorescent lamps is marked 886, the passport for the lamp says that it is designed to provide evacuation and backup lighting in the event of a power outage and is capable of maintaining autonomous mode from an internal sealed 6 V 1.6 Ah battery (this is almost a quote). It turns out that it does not work from a 220 V network, the network only recharges the battery and, one must assume that if the battery is completely discharged, there will be no lighting. I connect the lamp to the network and leave it on charge for the evening and night.
The next morning, the red "CHARGE" LED on the switch panel began to glow. But weakly - if you don’t look closely, it’s almost not noticeable. More than 10 hours have passed since the start of charging and, theoretically, it should burn much brighter. Although, perhaps, the lamp has some kind of system for turning off the charging current with an indication - no charge, no glow. I flicked the switch left and right, it didn’t light up. I unplug it, click it and it doesn’t light up.
I'm starting to disassemble the lamp. First I remove the light diffuser to inspect the lamp. The filaments are intact, the phosphor at both ends of the lamp has small ring darkening ( Fig.2).
Fig.2
I put the diffuser in place, remove the back cover ( Fig.3) and take out the “insides” ( Fig.4).
Fig.3
Fig.4
All wiring ( Fig.5) and I sketch all the places where the conductors are soldered to the printed circuit board ( Fig.6) and sign with a marker directly on the board - visible on Figure 4.
Fig.5
Fig.6
Since the board contains a transformer with a ferrite core, the circuit is most likely a low-voltage DC to high-voltage AC converter. There are no starters or chokes visible in the power supply circuits of the lamps; it seems that the lamps simply “ignite” during a high-voltage “breakdown” of the gas.
On the board you can see places where the green varnish has bulged, but the copper foil underneath is not deformed, which means that the green varnish fell off not due to overheating, but just like that. Fresh soldering is visible just in the places where the conductors going to the lamps are connected, but judging by the holes on the board, the conductors were soldered correctly. A swollen electrolytic capacitor is also noticeable ( Fig.7). I changed it right away, I couldn’t find the 220 µF/16 V rating, so I set it to 330 µF/25 V and soldered a 0.1 µF ceramic to its terminals on the print side. The capacitor is located near the transformer and is almost certainly connected to pulse currents (otherwise it would not “float”) and installing an additional ceramic capacitor that has lower reactance for pulse currents will make it easier to operate in the future.
Fig.7
Measuring the voltage at the battery terminals was not encouraging - the potential was slightly less than 3 V. I unsoldered the battery, connected the conductors to a laboratory power supply with a voltage set to 6.5 V. I clicked the switch, no reaction. I turned on the oscilloscope, poked the probe into different places on the board and, of course, into the legs of the low-voltage windings of the transformer - there was no generation anywhere. This means that we need to deal with the integrity of the parts. I turned everything off and unsoldered all the wires from the printed circuit board ( Fig.8 And Fig.9) – they will still fall off if the board is turned over multiple times.
Fig.8
Fig.9
On Figure 10 the marking “MD886” is visible. The numbers match the lamp markings, the letters do not. Nevermind.
Fig.10
A tester test of all semiconductor parts revealed a “dead” transistor (short circuit between the base and collector). A radiator is screwed to the transistor and it is logical to assume that it is the power switching element in the converter (transistor, not a radiator). The markings are not familiar, but search engines for the query “transistor 882” returned information on 2SD882. Well, okay, so be it.
I couldn’t find such a transistor at home, I read the datasheets and installed our own, Soviet KT972 ( Fig.11). I understand that the replacement is not entirely equivalent (ours is composite), however, after returning all the wires to their place, the circuit worked. The lamp lit up, but not very brightly. Although, perhaps, this is how a 6-watt fluorescent tube should shine with this method of igniting it. Changing the supply voltage in the range from 7 V to 5 V did not have much effect on the brightness, but, probably, the frequency of the converter changed, since a quiet whistle appeared in the transformer. The transistor is warm, but not hot.
Fig.11
While I was ringing the parts “for integrity”, I simultaneously sketched their connection ( Fig.12). Then I redrew it all in a normal “readable” form and got a diagram ( Fig.13) (the indicated voltages were measured and marked during the next battery charging after the lamp was repaired).
Fig.12
Fig.13
The circuit can be roughly divided into two parts - one, high-voltage, is responsible for charging the battery when the lamp is connected to a 220 V network, the other is converter, powered only by the battery and works only when 220 V is not supplied to the lamp.
On Figure 13 it can be seen that the alternating mains voltage passes through the current-limiting capacitor C1 and is supplied to the diode rectifier bridge VD1...VD4. Rectified voltage ripples are smoothed out by capacitor C2. The level of this voltage mainly depends on how charged the Bat1 battery is. Since its charging current passes through the diode VD6, then after the total voltage on Bat1 and on the diode VD6 approaches the opening threshold of the zener diode VD5, the currents will begin to be redistributed - the charging one will decrease, and the current through the zener diode will increase. This is how the battery is protected from overcharging. Connected to the circuits with rectified voltage are also the “CHARGE” mode indicator on the HL1 LED (with a current-limiting resistor R3) and a resistor divider R5R6, the voltage from which is supplied to the base of the transistor VT1, thereby “opening” it. The open transistor VT1, in turn, “locks” the transistor VT2, “shorting” the base-emitter junction VT2, thereby prohibiting the operation of the blocking oscillator of the converter. If the voltage in the 220 V network disappears, then capacitor C2 will discharge, transistor VT1 will “close”, the converter will start working, voltage will appear on the high-voltage winding of transformer Tr1 and the lamps will begin to glow. Of course, this will happen if the slide switch S2 (2 directions, 3 positions) is in one of the extreme positions, i.e. in normal operating mode. To check the functionality of the lamp connected to the network, there is a button S1 in the circuit - pressing it forcibly “closes” the transistor VT1 and starts the converter.
For the remaining elements of the scheme. Resistor R1 discharges capacitor C1 through itself after disconnecting the lamp from the 220 V network. R2 is a current limiting voltage for the zener diode VD5. There was no marking on the zener diode, but most likely in this circuit it should have a high power dissipation, for example, 5 W. A chain of resistor R4 and LED HL2 “BATTERY” - indicating the presence of supply voltage to the converter - turns on at any extreme position of switch S2. The same switch selects the ignition mode of one or two lamps and, in the case of operation with two lamps, increases the base current of transistor VT2 by connecting resistor R7 in parallel with resistor R8. The current of pulses arriving at the base VT2 from the winding of transformer Tr1 is limited by resistor R9. The capacitance of capacitor C4 selects the operating frequency of the converter - when working with one lamp (after installing the KT972 transistor), it turned out to be better to increase the capacitance of C4 by one and a half times - the current consumed from the battery decreased and at the same time the brightness of the lamp increased). Capacitor C5 is needed for the operation of the blocking generator (if one can say so, it is used to “short-circuit” to minus the pulses at the upper terminal of the base winding Tr1 and, accordingly, obtain pulses that are optimal in level based on VT2).
While there is no new normal battery, you can “look” at the old one - it is clear that it does not hold capacity, but you need to assess the degree of its inoperability and try to “bring it to life” with several successive charge and discharge cycles.
The battery measures 100x70x47 mm and has no markings other than letters and numbers on the top cover ( Fig.14). Search engines say that it is most likely lead-acid, sealed, maintenance-free, with a capacity of 4.5 A/h (and the passport for the lamp says that a battery with a capacity of 1.6 A/h is used).
Fig.14
On Figure 14 it is clear that someone has already tried to pry off the lid that blocks access to the insides - two slits have been scratched. I insert a thin, wide textolite screwdriver into the slot on the right edge and, with some effort, remove the cover ( Fig.15). Three rubber sealing caps are visible, placed on the necks of the jars. And since there are three of them, then, presumably, each bank is designed for a voltage of 2 V.
Fig.15
I remove the caps with tweezers ( Fig.16).
Fig.16
Then I connect the probe of the positive terminal of the voltmeter to the positive terminal of the battery, and use a crocodile clip on the negative probe to clamp the medical needle. Carefully, without effort, I lower the needle into the jar and touch its insides in different places ( Fig.17). The task is to touch hard conductive surfaces. The maximum voltage that the tester showed was about 0.5 V. Then, using a second needle, I also check the second can ( Fig.18) – the tester also shows 0.5 V.
Fig.17
Fig.18
And only when checking the third can, a normal voltage of 2 V finally appeared. In total, the total is the same 3 V that was measured at the stage of examining the interior of the lamp.
To charge the battery in a single can, a circuit was assembled according to Figure 19. Here, the ammeter shows the current flowing in the circuit (taking into account the current through the La1 light bulb), the voltmeter shows the voltage on the charging bank. The voltage on the power supply was set so that at the beginning of the charge the current through the can did not exceed 150 mA. The voltage on the bank was controlled with a VR-11A multimeter. When the value of 2.3 V was reached, switch S1 opened, the charge stopped and the discharge began to a voltage of 1.8 V. A total of four such cycles were carried out and after that the battery was fully charged. The lamp worked on it for just over five minutes - the time, of course, is not impressive, but considering that the battery had not worked at all before, the result of the training is visible. On Figure 20 shows the voltage measurement at the terminals after the next charge.
Fig.19
Fig.20
After turning on the lamp several times and charging, the lamp began to “diverge” and shine brighter and brighter ( Fig.21). I did not control the current consumption from the battery, but judging by the fact that the transistor is heating up in the same way as it was warming up, even if the current has increased, it does not affect the transistor - this is probably correct and good.
Fig.21
On Figure 22– indication when charging in the “OFF” switch position, on Figure 23– in the “One lamp” switch position. When the lamp is disconnected from the network, one tube begins to glow and only the green “BATTERY” LED remains lit ( Fig.24).
Fig.22
Fig.23
Fig.24
It is clear that the described repair case can be classified as “amateurish”, but, as it turned out, the electrical circuit is quite simple and understandable, there are few parts, the most difficult thing that can be is repairing the transformer. Although, probably, it’s also not a problem - desolder, disassemble the core, preheat it, count the turns and remember the winding direction, wind new ones, assemble everything and solder it.
Andrey Goltsov, Iskitim
List of radioelements
| Designation | Type | Denomination | Quantity | Note | Shop | My notepad | |
|---|---|---|---|---|---|---|---|
| Figure No. 13 | |||||||
| VT1 | Bipolar transistor | S9014-B | 1 | To notepad | |||
| VT2 | Bipolar transistor | 2SD882 | 1 | To notepad | |||
| VD1...VD4, VD6 | Rectifier diode | 1N4007 | 5 | To notepad | |||
| VD5 | Zener diode | 1N5343B | 1 | see text | To notepad | ||
| HL1 | Light-emitting diode | L-513ed | 1 | red | To notepad | ||
| HL2 | Light-emitting diode | L-513gd | 1 | green | To notepad | ||
| C1 | Capacitor | 2 µF | 1 | film 400 V | To notepad | ||
| C2, C3 | Electrolytic capacitor | 220 µF | 1 | 16 V | To notepad | ||
| C4, C5 | Capacitor | 10 nF | 2 | film 100 V | To notepad | ||
| R1 | Resistor | 560 kOhm | 1 | To notepad | |||
| R2 | Resistor | ||||||
The SKAT LT-301300-LED-Li-Ion lamp from BASTION with a built-in lithium-ion battery and increased luminous efficiency is designed to illuminate escape routes in the event of an emergency at a protected facility or during power surges in the workplace. SKAT LT-301300-LED-Li-Ion is equipped with 30 LEDs with increased brightness. The backup power supply ensures uninterrupted operation of the lamp in the event of a power outage for 3 to 6 hours.
The SKAT LT-301300-LED-Li-Ion lamp has two operating modes and a brightness control that allows you to adjust the lighting power depending on the characteristics of the room. The robust and compact housing is easy to install at the workplace. Ceiling mount included.
Main features of SKAT LT-301300-LED-Li-Ion
- 30 bright LEDs
- Reserve time up to 6 hours
- Li-ion battery
- 2 operating modes
- Wall and ceiling mounting
Technical characteristics of SKAT LT-301300-LED-Li-Ion
| Supply voltage 220 V, frequency 50±1 Hz with variation limits | 187…242 V |
| Number of LEDs in the lamp | 30 |
| The power of light | 30x2500 mcd |
| Backup battery built-in Li-ion | type 18650 voltage 3.7 V capacity 1200 mAh |
| Battery capacity | 1.2 Ah |
| dimensions | 270x65x52 mm |
| Weight | 0.26 kg |
| Operating temperature range | 0 °С…+40 °С |
| Relative humidity at 25 °C | 85% |
| Degree of protection by shell according to GOST 14254-96 | IP20 |
Instructions for the lamp SKAT LT-301300-LED-Li-Ion Bastion
Download instructions
*.PDF format
file size< 187 Кб
You can buy an emergency lighting lamp SKAT LT-301300-LED-Li-Ion Bastion with delivery or pickup at a low price. Our specialists will help you select the necessary equipment. We offer high-quality equipment with a 1-year warranty.
The SKAT LT-2330 LED luminaire is used in emergency lighting systems for facilities in the event of a main power failure. Safety lighting is used to continue carrying out important work during a power outage, and evacuation lighting is used to highlight passageways. This lamp turns on only when there is no mains voltage and cannot be used as a regular lamp. It is constructed using 30 LEDs, which feature an increased light output of 2,500 mCd. The glow power switch can switch the lamp to half power.
SKAT LT-2330 LED is installed for emergency lighting of exits from premises and evacuation routes in the event of a power outage at the site. Increased light output, provided by a matrix of 30 powerful LEDs, guarantees excellent illumination of a large area.
It is used as a reliable autonomous source of backup lighting with a built-in rechargeable battery.
2 operating modes:
The "charge" mode is activated when there is a 220 V AC network; the LEDs are not turned on and the CHARGE indicator is on;
The "reserve" mode is activated when the 220 volt alternating voltage is lost; LEDs are on.
The plastic housing contains a power switch for the LED lamp.
The battery life at low power reaches 8 hours, and at high power up to 4 hours.
The lamp protects the battery from overcharging and deep discharge.
Wall or ceiling mounting option is possible using the overhead method.
Stylish modern housing design with a transparent cover that protects the LED matrix.
Characteristics
Luminous intensity 2500 mcd
Number of LEDs 30
Power consumption about 18W
Battery recharge time is about 24 hours
Glow color white
Battery capacity 1.2 Ah
Battery life:
At low power 8 hours
At high power 4 hours
Method of installation of the invoice
Supply voltage 187...242 V AC
Dimensions 265x68x55 mm
Weight 0.39 kg
Material plastic
Case color white, gray
The SKAT LT-2330 LED emergency lamp is powered from an AC mains voltage of 187~242 V and supports autonomous operation due to an internal rechargeable battery with a capacity of 1.2 Ah. If there is voltage in the mains, the battery charging mode is active; if the mains is lost, the lamp turns on automatically. The operating time of the lamp from the battery is 4 hours (8 hours at half power). The battery is protected from deep discharge and overcharging. This model supports the lamp operating mode - pressing the TEST button simulates a loss of mains voltage. Bastion engineers have provided two options for wall mounting of the SKAT LT-2330 LED luminaire, as well as the possibility of ceiling mounting.
Powerful lamp for emergency lighting with built-in battery BASTION SKAT LT-2330 LED. Designed to illuminate escape routes in the event of an emergency at a protected facility or during power surges in the workplace. SKAT LT-2330 LED is equipped with 30 LEDs and has two adjustable operating modes. The power switch allows you to adjust the brightness of the lighting depending on the characteristics of the room.
SKAT LT-2330 LED is equipped with a backup power supply that ensures uninterrupted lamp operation for 4 to 8 hours in the event of a power failure. The compact case allows you to easily place the device at your workplace. Ceiling mount included.
Main features of SKAT LT-2330 LED
- 30 bright LEDs
- Reserve time up to 4/8 hours
- Battery protection from overcharge and deep discharge
- 2 operating modes
- Wall and ceiling mounting
Technical characteristics of SKAT LT-2330 LED
Instructions for the SKAT LT-2330 LED Bastion lamp
Download instructions
*.PDF format
file size< 193.5 Кб
You can buy an emergency lighting lamp SKAT LT-2330 LED Bastion with delivery or pickup at a low price. Our specialists will help you select the necessary equipment. We offer high-quality equipment with a 1-year warranty.
