arudino pin canfigaretion

selar machine photos

 number printing unit

main motor and drive gear system

hearting system

over load relay

over load relay

over load -විදුලි මෝටරයක් යම්අවස් තාවකදී ධාවනය සදහා ලබාගන්නා ධාරාව නියමිත පූමානය ඉක්මවුව හොත් මෙමගින් විදුලි පරිපතය විසන්දි කරනුලබයි

Full Wave Shunt Regulator Circuit for Motorcycle

Shunt regulator is a device which is used for regulating voltage to some fixed levels by means of shunting. Normally the process of shunting is done by grounding the excess voltage, just as zener diodes do in electronic circuits.

However one bad aspect with such regulators is the generation of unnecessary heat. The reason for heat generation is the principle of its operation where the excess voltage is short circuited to ground.

The above practice may be implemented by simpler and cheaper means, but cannot be considered efficient and advanced. The system is based on destroying or killing energy instead of eliminating or inhibiting it.

The circuit of a motorcycle shunt regulator discussed in this article takes a completely different approach and restricts the in-flow of excess voltage instead of "killing" energy and thus stops the generation of unnecessary heat.

The circuit functioning may be understood as under:

When the mobike is started, voltage enters across the P-channel mosfet source/drain pins due to the gate trigger that becomes available via R1.

The moment the high voltage reaches R3, which happens to be the sensing input of the opamp, pin#3 of the IC senses an increased voltage.

As per the set reference at puin#2, the instantaneously reacts to the situation and the result puts the output of the IC to a high logic level.

The immediate high logic pulse restricts the negative base trigger of the mosfet, switching it OFF at that particular instant.

The moment T1 switches OFF, voltage at the junction of R3/R4 reverts to the original condition, that is the voltage here now drops below the reference level......this instantly activates the opamp output with a low logic signal which in turn switches ON T1 back into action.

The process repeats at a very rapid speed, keeping the output voltage marked with +/- at a constant level determined by the setting of R2/Z1 and R3/R4.

The above principle utilizes voltage inhibition technique of the excess voltage instead of shunting it to ground, thus saves precious power and also helps to control global warming in some way.

Parts List

R1, BR2 = 10Amp bridge rectifier

R1 = 1K
D1 = 1N4007
C1 = 100uF/25V
IC1 = IC741
T1 = mosfet J162

R2/Z1, R3/R4 = 

photos

indecator bulb

mccb 1200amp

atys switch

pcb drilling maching

Drilling

In this step, any holes or vias in the PCB are drilled out. For this step you will need: a drill press that can run at 2000+ RPM, high-speed carbide wire-gauge drill bits. This step takes 3-10 minutes, depending on number of holes in pcb.
If your PCB is FR4 laminate, you may want to find a dust mask for this step, since fiberglass dust is carcinogenic. Chances are, you're using paper phenolic which is much safer. There is a box of HSS carbide drill bits in a box underneath the etcher, they are packaged in plastic boxes of 10. Find the boxes of closest size to your board holes. In general, .020"/75ga is good for RF vias, .028"/70ga is good for signal vias, .035"/65ga is good for DIP/LEDs/Resistors/Capacitors, etc., .042"/58ga is good for TO-220/heavier diodes/etc., .060"/53ga for heavier wires and power components, and .086"/44ga for mounting holes or anything else. Other drill sizes are available for purchase, of course.

Left, these are inexpensive resharpened drill bits $7.50 a box. Right, 70 gauge is as small as you'll need

Place the first drill bit in the chuck, and tighten it well. Find a piece of wood to place underneath the board for support. While the drill is running, adjust the speed to 2000RPM or higher.

The drillpress in the media lab shop is more than sufficient, adjust it only while running

Drill all holes of one size at a time. Try to position the drill bit right in the center of the hole, or at least, try not to drill through any copper traces. The drill bits might break, especially if they sub-35mil. Holding the board steady while drilling through it helps. The bits only cost 75 cents so just throw them away when broken, but if you break more than 5, you should purchase a replacement set.

You can drill a hole a second if you dont clamp down the board, but breakage is more likely

After all the drilling, replace the bits in their boxes, and put the box back underneath the etcher.

Shearing

In this step, the tiled layouts are seperated. For this step you will need a metal shear (this step could also be done with a band saw.) This step takes 2 minutes.
Shear or cut the good boards out, leaving a few mm on each edge. The edges may be filed or sanded.

genertor starer digram

genertor wring digram

resistor color code

SENSETIVE ELECTROINC ITEM-අලුත්ම සංවේදී මෙවලම්

Solar Inverter Circuit

How to Make a Solar Inverter Circuit

Solar power is abundantly available to us and is free to use, moreover it’s an unlimited, unending natural source of energy, easily accessible to all of us. We have discussed how to use solar panels for generating electricity from solar or sun power, in this article we are going to discuss a simple arrangement which will enable us to use solar energy for operating our household appliances.

A solar panel is able to convert sun rays into direct current at lower potential levels. For example a solar panel may be specified for delivering 36 volts at 8 amps under optimal conditions, but we cannot use this magnitude of power for operating our domestic appliances, because these appliances can work only at mains potentials or at voltages in the ranges of 120 to 230 V. Further more the current should be an AC and not DC as normally received from a solar panel.

We have come across a number of inverter circuits posted in this blog and we have studied how they work.

Inverters are used for converting and stepping up low voltage battery power to high voltage AC mains levels.

Therefore inverters can be effectively used for converting the DC from a solar panel into mains outputs that would suitably power our domestic equipment.

Basically in inverters, the conversion from a low potential to a stepped up high mains level becomes feasible because of the high current that’s normally available from the DC inputs such as a battery or a solar panel. The overall wattage remains the same.

For example if we supply an input of 36 volts @ 8 amps to an inverter and get an output of 220 V @ 1.2 Amps would mean that we just modified an input power of 36 × 8 = 288 watts into 220 × 1.2 = 264 watts. Therefore we can see that it’s no magic, just modifications of the respective parameters.

If the solar panel is able to generate enough current and voltage, its output may be used for directly operating an inverter and the connected household appliances and also simultaneously for charging a battery. The charged battery may be used for powering the loads via the inverter, during night times when solar energy is not present.

However if the solar panel is smaller in size and unable to generate sufficient power, it may be used just for charging the battery, and becomes useful for operating the inverter only after sunset.

Referring to the circuit diagram, we are able to witness a simple set up using a solar panel, an inverter and a battery. The three units are connected through a solar regulator circuit that distributes the power to the respective units after appropriate regulations of the received power from the solar panel.

Assuming the voltage to be 36 and the current to be 10 amps from the solar panel, the inverter is selected with an input operating voltage of 24 volts @ 6 amps, providing a total power of about 120 watts.

A fraction of the solar panels amp which amounts to about 3 amps is spared for charging a battery, intended to be used after sunset.

We also assume that the solar panel is mounted over a solar tracker so that it is able to deliver the specified requirements as long as the sun is visible over the skies.

The input power of 36 volts is applied to the input of a regulator which trims it down to 24 volts.

The load connected to the output of the inverter is selected such that it does not force the inverter more than 6 amps from the solar panel. From the remaining 4 amps, 2 amps is supplied to the battery for charging it.

The remaining 2 amps are not used for the sake of maintaining better efficiency of the whole system.

The circuits are all those which have been already discussed in my blogs, we can see how these are intelligently configured to each other for implementing the required operations.

A MINI solar inverter circuit with relay changeover is discussed HERE





For Charging Batteries up to 250 AH

The charger section in the above circuit may be suitably upgraded for enabling the charging of high current batteries in the order of 100 AH to 250 AH.

An outboard transistor TIP36 is appropriately integrated across the IC 338 for facilitating the required high current charging.

The emitter resistor of TIP36 must be calculated appropriately otherwise the transistor might just blow off, do it by trial and error method, start with 1 ohm initially, then gradually go on reducing it until the required amount of current becomes achievable at the output.

LED Emergency Light Circuit

Simple LED Emergency Light Circuit

The article describes a very simple homemade emergency light circuit that can be used during power failures and outdoors where any other source of power might be unavailable. The circuit uses LEDs instead of incandescent lamp, thus making the unit very power efficient and brighter with its light output. Moreover, the circuit employs a very innovative concept especially devised by me which further enhances the economical feature of the unit.

Let’s learn the concept and the circuit more closely:

The concept:

We know that LEDs require a certain fixed forward voltage drop to become illuminated and it is at this rating when the LED is at it’s best, that is voltages which is around its forward voltage drop facilitates the device to operate in the most efficient way. 

As this voltage is increased, the LED starts drawing more current, rather dissipating extra current by getting heated up itself and also through the resistor which also gets heated up in the process of limiting the extra current.

If we could maintain a voltage around an LED near to its rated forward voltage, we could use it more efficiently. That’s exactly what I have tried to fix in the circuit.

Since the battery used here is a 6 volt battery, means this source is a bit higher than the forward voltage of the LEDs used here, which amounts to 3.5 volts. The extra 2.5 volts rise can cause considerable dissipation and loss of power through heat generation.

Therefore I employed a few diodes in series with the supply and made sure that initially when the battery is fully charged; three diodes are effectively switched so as to drop the excess 2.5 volts across the white LEDs (because each diode drop 0.6 volts across itself).

 Now as the voltage of the battery drops, the diodes series are reduced to two and subsequently to one making sure only the desired amount of voltage reaches the LED bank.

In this way the proposed simple emergency lamp circuit is made highly efficient with its current consumption, and it provides backup for a much longer period of time than what it would do with ordinary connections.

Efficient, Automatic, White LED Emergency Light Circuit Description:

Referring the shown simple LED emergency light circuit, we see that the circuit is actually very easy to understand, let’s evaluate it with the following points:

The transformer, bridge and the capacitor forms a standard Power supply for the circuit. The circuit is basically made up of a single PNP transistor, which is used as a switch here.

We know that PNP devices are referenced to positive potentials and it acts like ground to them. So connecting a positive supply to the base of a PNP device would mean grounding of its base. Here, as long as mains power is ON, the positive from the supply reaches the base of the transistor, keeping it switched off. Therefore the voltage from the battery is not able to reach the LED bank, keeping it switched off.

In the meantime the battery is charged by the power supply voltage and it’s charged through the system of trickle charging.

However, as soon as the mains power disrupts, the positive at the base of the transistor disappears and it gets forward biased through the 10K resistor.

The transistor switches ON, instantly illuminating the LEDs.

Initially all the diodes are included in the voltage path, and are gradually bypassed one by one as the LED gets dimmer.

HAVE ANY DOUBTS? FEEL FREE TO COMMENT AND INTERACT.

Parts List for the proposed LED emergency light circuit

R1 = 10K,

C1 = 100uF/25V,

D1, D2 = 1N4007,

D3---D6 = 1N5408,
T1 = BD140

Tr1 = 0-9V, 500mA,

LEDs = white, hi-efficiency, 5mm,

S1 = switch with three changeover contacts.


In response to the suggestion of one of  our avid readers, the above automatic LED emergency light circuit has been modified and improved with a second transistor stage incorporating an LDR trigger system. The stage renders the emergency light action ineffective during day time when ample ambient light is available, thus saving precious battery power by avoiding unnecessary switching of the unit.

Circuit modifications for operating 150 LEDs, requested by SATY:

Parts List for the modified emergency light circuit

R1 = 220 Ohms, 1/2 watt
R2 = 100Ohms, 2 watts,
RL = All 22 Ohms, 1/4 watt,
C1 = 100uF/25V,
D1,2,3,4,6,7,8 = 1N5408,
D5 = 1N4007
T1 = AD149 or similar,
Transformer = 0-6V, 500mA


The following circuit shows how a low voltage cut off circuit can be included in the above design for preventing the battery from getting over discharged.

Power Supply Circuit with Emergency Backup

The circuit shown below was requested by one of the readers, it is a power supply circuit which trickle charges a battery when AC mains is available, and also feeds the output with the required DC power via D1.  Now, the moment AC mains fails, the battery instantly backs up and the compensates the output failure with its power via D2.


When input Mains is present, the rectified DC passes through R1 and charges the battery with the desired output current,  also, D1 transfers the transformer DC to the output for keeping the load switched on simultaneously.

D2 remains reverse biased and is not able to conduct because of higher positive potential produced at the cathode of D1.

However when mains AC fails, the cathode potential of D1 becomes lower and therefore D2 starts conducting and provides the battery DC back up instantly to the load without any interruptions.

Parts List for an emergency light back up circuit

All Diodes = 1N5402 for battery up to 20 AH, 1N4007, two in parallel for 10-20 AH battery, and 1N4007 for below 10 AH.

R1 = volt/charging current (Ohms)

Transformer Current/Charging current = 1/10 * batt AH

C1 = 100uF/25


Using NPN transistors


The first circuit can be also built using NPN transistors, as shown here:

ATS circuit

Circuit Description

The ATS circuit or automatic relay changeover for generator/ mains circuit as shown below can be understood as follows:

For so long as home mains is present T1 base receives the rectified low voltage DC and keeps T2 base grounded.

With T2 base grounded REL1 is held switched OFF along with REL2, REL3 and REL4, the whole circuit thus stays switched OFF.

With REL4 deactivated, the DPDT holds the home mains supply with the load and the load gets powered via its N/C contacts.

Now in a situation when home mains fails, T1 is inhibited from its base drive and it instantly stops conducting.

With T1 OFF, T2 now activates, switching ON REL1, which in turn activates the LPG solenoid valve for allowing the fuel to reach generator combustion chamber.

After a few seconds delay T3/REL2 also activate pushing ON the choke solenoid into start position. The delay may be fixed by the tweaking the values of R7, C3.

REL2 activation switches ON the 555 astable which starts counting upto 5 seconds and triggers T4/REL3 so that the generator starter motor begins cranking the gen.

The astable allows this to happen for 5 seconds, if the generator starts, a 12V supply from a 12V adapter connected at the output of the generator feeds T6 base and disables the 555 astable.

The above 12V from the gen also activates the 4060 timer/latch which counts for about 10 seconds after which its pin#3 goes high.

The pin#3 high pulse latches the IC and also feeds T5 which deactivates REL2 so that the choke solenoid is pulled back to "close" position.

The 4060 output also simultaneously activates T7/REL4 making sure that the load now gets connected to the generator AC via N/O contacts of REL4.

Now suppose due to some fault, the cranking of the generator starter fails to initiate the generator, the astable makes three attempts with 5 seconds interval between each try.

Since the above pulses also reach IC4017 counter, after three pulses the IC4017 output sequence reaches its pin#10 which instantly latches itself due to a high at pin#13, and also disables the 555 astable by grounding its reset pin#4 via T6.

REL3 now stops feeding the crank mechanism.

An additional transistor driver/RELAY may be configured with pin#10 of IC 4017. The N/O contacts of this relay then could be wired with an alarm for the required warning in case the cranking attempts fails to start the generator.

When mains AC returns, T1 receievs the atached 12VDC at its base, however due to the presence of R2, D3, C5, T1 is restricted from the base voltage for a few seconds, until C5 charges.

In the meantime T7 is disabled and REL4 reverted to home mains position by T8, this happens as soon as mains returns, so that the generator gets immediately unloaded from the connected appliances.

Parts list for the above automatic transfer switch or ATS circuit

R1, R4, R5, R6, R7, R8, R9, R10, R11 = 10K
R2, R3 = 100K
C4 = 0.1uF
C1----C5 = timing capacitors, can be between 10uF to 100uF
All transistors are BC547
All diodes are 1N4007
REL1---REL3 = 12V/10 amps/400 ohms
REL4 = 12V/40amps or as per load specs