HindlePower offers a variety of industrial battery chargers and SCR Rectifiers for any of your business needs. Best Battery Selector. Steering Diode Assembly. Steering diode interconnection device to provide battery/charger protection and redundancy where two dc power sources are connected to facility loads.
. Overheat chargingThe important, battery does not like hot! At all time, do not use or store them in too heat area.OR If while use may short circuit or high current use them will too hot. While charging does not quick charge with high current and high voltage. DC voltage only!We must charge them with DC voltage only.
Overvoltage chargingNormally, the battery manufacturer usually prints the appropriate voltage.We should use a constant voltage charge.—12V battery maximum voltage of 14.8V, Standby use is 13.8V—6V battery maximum voltage of 7.5V, Standby use is 6.8V. High current fast chargeBut hot—So you should use initial current less 30%. For example, 12V/7AH battery you should the initial current less 2A. If we use 1A, the battery will be full for about 7 hours. No long timeAlso, If you charge it for too long times. The battery is also too hot.
Thus, When the battery is full, stop charging it.These two circuits help make your life easier. Page Contents, Click.Simple Automatic battery charger circuitThis is the first automatic battery charger circuit. We use the concept of the circuit: not using ICs and complicated devices. Use existing products to use more benefits.We can use this circuit for all battery. Just have to understand Battery charging requirements only.
It is designed for 12V batteries. But if you understand the working principle already. I believe you can definitely adapt for a 6V battery or others. You should use an input voltage of 15-volts or 1.5 times of a battery voltage. Most importance—Should use charger current 10% of battery current. For example 2.5Ah battery. Use the charging current 0.25A.
It will take 10-12 hour for full.How it worksFirst of all, I think “WhenCharge? And When stop?”Normally we should charge the battery if the voltage is lower than 12.4V. Then the battery voltage rises and the voltage maximum 14.4V. We need to cut off the charging current.Secondly, we need to use a comparator circuit.I often use IC-op-amp such as LM339, LM311, LM324, LM301.
But sometimes we cannot buy them.And This our working is simple style only.In the begin, we learn a basic principle of electronic parts. Meet Zener DiodeI like use Diode, Zener diode, which they are both valves for electrical currents. The Current will flow one way. But the Zener diode is connected backward. It then blocks current until the voltage exceeds a certain level.I try to test them with the Zener diode 12-volts the current will flow through it when a voltage higher than 12V.So, I use Zener diode for detects voltage over than 13V to control stop charger system.Relay and SCR cut-off batteryThen, I use a relay to control the current to a battery. Because of cheap and used easily.Next, I use a SCR for uses as quick control switch.Simple automatic cut off battery chargerComes to look in the circuit. I use it for 12V 7AH battery and lower.
So the charging current is 2A.So I use a 2A, 12V transformer in the unregulated power supply. In load or while in charge is 13V to 15VDC.Suppose, the voltage battery is 12.4V. The relay does not work. The charging current flows continuously through the battery.Until the voltage of the battery rises up to 13.8V.
Starts to has the current flowing through Zener diode to Bias SCR1.The SCR1 is working. Then replay also runs, pull in the NO and C connecting.So no current flow to the battery. How to setting and useYou can watch the video below I test it. This projects will always cut off the battery.
When the voltage drops across it are 13.6V down.Then LED2 (yellow) glow brightly. While the relay will pull out from the contact NC-C. Which no current to battery and voltage lower down.Then you can charge again with pressing SW2 to reset, recharge them again. High current chargingIf you want to charge the high current battery. For example, 45Ah battery. You should use the current less than 5A.
And less than 15A current.Also, you need to use a high current power supply. The components inside are high current. For example 10A-15A transformer, 25A bride Diodes, 20A Relay and more.I think this circuit is not suitable for high current battery.
Because it may error charging. You need to use a constant voltage charge in PWM mode. Automatic OFF 12V Battery Charger by power SCRThe circuit above may error and hard to set. I suggest an Auto dry battery charger using SCR for 12V battery.
Also, it uses the 6V battery. It looks like the above circuit.
The Zener diode and SCR are main parts. But the SCR works instead of the relay. The SCR is working in DC pulse on filters with a capacitor.How this circuit worksAs circuit below. To begin with, an AC220V will flow to a transformer to transform to 15 volts.
Then, flow to bridge diode to rectifier AC to DC pulse 15V. The LED1 is a power indicator of the circuit. Buy many components at AmazonBeginning SCR1 is working. Because the 15V flow to R3, to limit the current to decrease and flow through to diode D5.It protects the reverse voltage before bias to lead G of SCR1.When SCR1 conducts, make the 15V flows through lead K to a positive battery terminal.Ideally, SCR1 will conduct current and stop current alternately very fast with a frequency of 100 Hz.Since the 15V voltage from the bridge diode is full wave rectifier. So the output frequency of 50Hz+50 Hz. The current of this feature is a continuous positive half of the sine wave.Which it is different from the voltage with capacitor filter, that is smooth as a straight line.So SCR1 does not conduct the current all time.
When there is positive voltage to bias at lead G.Since the waveform of voltage is DC pulse, not smooth.The SCR will stop conducting current. If disconnecting is not a positive voltage.Then, the positive voltage waveform comes to SCR1 again. It will start conduct currents again, this was reversed with a frequency 100 Hz. Battery level monitoringTo begin with, the positive battery voltage flows through R2 to reduce current.
And, C1 will filter a current to smooth.Second, the current flows through VR1 to divide voltage down. Then, the Zener diode-ZD1 pass an overvoltage to bias lead G of SCR2.We adjust a level of VR1 to set a full battery. Until voltage at negative of ZD1 is more than 6.8V or about 7.3V.After that, ZD1 is saturation voltage collapse flow through to feed lead G of SCR2.
It causes SCR2 to conducts current. By R4 is a helper to SCR2 extraordinary stable work.When SCR2 work, causes a negative voltage flows to lead K to A. It results to LED2 glow.And the same time SCR1 will stop conducting current.Pinout of TO-220 and TO-92 of SCRsSince lead G of SCR1 get negative voltage from SCR2 there. In the case of battery is lower voltage, causes the voltage at negative of ZD1 is lower than 6.8V.It makes lead G of SCR2 does not get positive voltage. But it can get only negative voltage through R4, result SCR2 does not conduct current.The parts list0.5W Resistors5%R1, R5: 2KR2: 1.5KR3: 560ΩR4: 10KVR1: 10K PotentiometerC1: 100uF 25V Electrolytic capacitorSCR1: 2N6397SCRSCR2: EC103 or 2N5060SCRZD1: 6.8V 1WD1-D4: 1N5404DiodeD5: 1N4002DiodeLED1, LED2: 5M LED as you wantPCB, and others, etc. How to make and setting. After you get all the components ready.
Then, we soldered it successfully on PCB as Figure next checked again. For example, The device has a positive – negative. Are they correct polarity?The component layout of Dry battery chargerSoldering point of dry battery chargerComplete assembly all parts on PCBFully 12v battery 2.5A. To Safety, the first step, find a full battery voltage be connected to the circuit to correct polarity. Apply AC220V. Next, adjust VR1 clockwise until LED2 go out. To rotate VR1 clockwise slowly until LED2 light up, then stop immediately.
Do not too much rotating. The principle of LED2 will light up when battery voltage until full.
So, at the first time, the battery needs to be really full voltage.Note:I am sorry, I cannot show you the PCB layout. But you can use the perforated board.Please watch the video below to increase understand this project.Circuit modificationThis circuit can change the battery voltage of 3 sizes 6V, 9V, 12V.
We can change each value parts as a neat charged battery.In a normal circuit, we use with 12V battery. For example, Look at the chassis battery is stated as 12V 20AH. The meaning is this can power the currents of 20 amps per hour.When you know voltage at the battery is charged, Now I have to choose the transformer to be used.
Currents transformers used can be selected from 3A. 6V battery; Output transformer voltage: 9V;—Zener diodes voltage: 3.3V; —R3 and R5: 1K. 9V battery; Output transformer voltage: 12V;—Zener diodes voltage: 4.7V; —R3 and R5: 1.5K. 12V battery; Output transformer voltage: 15V;—Zener diodes voltage: 6.8V; —R3 and R5: 2KClick to look more:Easy Many circuits easy for you.
Please for those interested in the second charger: The Automatic cut-off 12V Battery Charger using SCR:Below is the detailed explanation of how it works.When the rectified input dc voltage to the charger circuit is supplied, the LED D1 glows.After the voltage input is supplied, current flows through R3 and diode D3 to bias the gate terminal (G) of SCR1. The SCR1 then conducts, allowing the outward voltage flow from its cathode (K) to the positive terminal of the battery to be charged. SCR1 conducts and stops current alternately with very fast frequency of about 100Hz. It will stop conducting current when power supply is disconnected.
The current from the positive terminal of the battery being charged, then flows through R2 and get filtered by the capacitor C1. The variable resistor VR1 together with R2 divide the battery voltage for the zener diode ZD1. The current then flows to bias the gate (G) of SCR2.When the battery voltage is low (i.e. Below 13.6v), the zener diode (ZD1) voltage is below 6.8V (due to the voltage division), and because this voltage is below the zener breakdown voltage, positive current (clock pulse) is applied at the gate of the SCR2 and it starts conduction in a forward bias.When the battery charge voltage is 13.6v and above, the SCR2 receives a negative pulse from the zener diode (ZD1) and it will not conduct. The gate G of SCR1 also gets negative voltage from SCR2 and will cease to conduct current to the battery being charged.
Hence terminates the charging process of the battery. When this happen, a negative voltage from SCR2 will complete the circuit of LED2 and as a result, it glows.The value of VR1 and the voltage value of the zener diode are used to determine the voltage limit of the battery to be charged.
When VR1 is adjusted until voltage at negative of ZD1 is 6.8V, it means the battery to be charged will be cut off at 13.6v.Important Definitions:.A Silicon-Controlled Rectifier, or SCR, is essentially a Shockley diode with an extra terminal added. This extra terminal is called the gate, and it is used to trigger the device into conduction by the application of a small voltage.A Zener diode is a diode which allows current to flow in the forward direction in the same manner as an ideal diode, but also permits it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage. Hi,Great site and a lot of good information, thank youQuestion:1. I am interested in how efficient this charger is. I am looking for the lowest possible efficiency with the largest electron emission, into the surrounding environment, from the charging circuit to the battery itself.I would imagine a capacitor change would be part of this equation along with a long distance wire from circuit to battery?Thank youBtwI am certainly willing to help you with editing your text/grammar if you are interested, for free of courseMike,.
In the battery charger ” Using Auto dry battery charger using SCR” circuit above, wanted to clarify regarding the maximum current which would pass through SCR1. Assuming we are connecting a discharged Lead Acid battery. Then when the circuit is powered ON, the peak AC voltage at the anode of the SCR1 would be 21V (15V rms). This would forward bias the SCR1 since cathode is at zero voltage (as battery output is zero).
The Gate of SCR1 is at higher potential than Cathode and hence SCR1 would conduct. At this stage since the internal resistance of a battery is in the range of 20-50 milli ohm. The current which would pass through SCR and battery as per ohm’s law would be approx.
20V/20 milli ohm (assuming 1V drop across SCR in conduction phase). This would be a very large current which could potentially damage the SCR/battery. Is there something I am missing here?. Hi,Thank you for submitting such interesting charging circuit: I have built the circuit and it is working fine except for one thing: LED2 (which is in series with SCR2) is switching on faint when there is no battery connected. Also when the battery is fully charged the same LED does not switch on bright like the one in your video: I built circuit on veroboard and I am using SCR1=TIC126D and SCR2= 2N5062 and I built 6V version with transformer = 9V, zener =3.3V and R1 and R5 =1K; what do you think is the problem please?Thank you very much for your help.