Need Help on designing Super capacitor Tester

Thread Starter


Joined Dec 19, 2013

I need an urgent help me to design a super capacitor tester. The details are as given below

This document describes the prototype functioning of capacitor board Tester.

The Capacitor board tester is micro controller based testing equipment which can test the proper functioning of Equivalent a super capacitors of 9.5 F.

NOTE: ( The test is for one single board consisting of 37 capacitors of 350 F connected in series )
v General Testing Procedure

1. On charge testing: In this test the Capacitor board is subjected to a charging through a constant voltage and constant current source of 80 V and 5 Amp respectively. The moment the charge reaches 80V the microcontroller stops charging the capacitor board and displays and records the time taken by board to reach the 8o v. The time to reach 80v has to be with permissible limits initially set of a typical functional board.

2. Discharge Testing: Once the capacitor board is charged to 80 V. The discharge characteristics of the capacitor board are tested. The charged capacitor board through microcontroller is subjected to discharge via 7 Ohm, 500 W resistor for pre-designated time and the drop in voltage is noted. The drop in the voltage is displayed and recorded and it has to be in within permissible limits which have been initially set for board to be declared functional.

Functional Diagram: The approx lookalike functional diagram is shown below:

The various connectors are labelled in the diagram below:

1. LCD Display which will show
a. Voltage display across Capacitor
b. Time display in sec
c. Current Display in Amp
2. Start switch for automatically starting the charging/Discharging Test
3. Probes/Connectors for Capacitor Board
4. Power on /Off Switch
5. Power LED
6. Internal Admin Panel Or it can be designed on external board
a. SEL: Selector switch for No Load ( NL) test OR With Load Test
b. Selection Indicator LED, NL: Charging test
c. Selection Indicator LED, With L: Discharge test
d. M/V, S/mV, Set: Micro switches for setting Discharge time / Voltage selector in Minutes/V and Sec/mV

3. Before testing the test parameters are set by admin using the admin Panel (6) as given below:
a. The device is switched on
b. Select button SEL is pressed
c. LED NL gets on and “from” time needs to be entered using M/V, S/mV, buttons in Mins and Sec.
d. The entered value is shown on LCD
e. After entering the time set button need to be pressed
f. After pressing set button the time is set and registered in microcontroller and LCT prompts user to enter “to” time.
g. User sets the “To” time and press set button. The time range is registered in microcontroller and the shows on LCD. Both time ( from – To ) are shown on LCD indicating completion of time feeding. This time range is the time a good capacitor board should generally take to charge.
h. Now user presses SEL button again for setting the discharge time for the capacitor and the permitted value of drop in Voltage across capacitor. The green LED (with L) glows up indicating the setting up of discharging with load.
i. The user sets the discharge time using M/V, S/mV, buttons in Mins and Sec and presses SET button. The time set is shown on LCD.
j. The LCD now prompts asking for setting up of range of discharge voltage .
k. User Using micro switches M/V, S/mV, buttons the voltage range is selected and user presses set button.
l. The set voltage range is now displayed on LCD

4. There is also a requirement of showing the pre-set parameters using select (6) button.

5. Test sequence:
a. The capacitor ends are connected across the probes
b. Start button is pressed.
c. The LCD displays the preset parameters and capacitor board starts discharging through a series resistance till the voltage across capacitor becomes 0V.
d. Once the voltage across capacitor reaches 0 V the capacitor starts charging and he charging current is restricted via constant current source at 5 amp internally and voltage rises. The rise in voltage and time taken in mins and sec are shown on display. Moment it reaches 80 V the corresponding time is displayed and captured.
e. The microcontroller now automatically connects the capacitor to a discharge circuit via a relay and a series resistance of 7 Ohm 500w. The drop in voltage is recorded for the given time( set initially )
f. The result obtained both during and discharging is displayed on LCD.
g. The capacitor is fully discharged automatically .

6. Test result
a. The charging time is compared with the stored time value
b. The drop is voltage recorded is compared to the voltage limit set for the set discharge time
c. If both a. and b. are satisfied the capacitor is declared functional by green LED or else red indicating faulty capacitor board.
d. The final result is also on LCD display

Note : 1. Power supply of constant 80V 5 Amp in inbuilt inside.
2. The current soured being constant at 5 amp may not be shown however it will be good if we can show it on LCD.
3. The admin Panel (6) can be a externally fitted too.

Can any one help me with the circuit diagram?



Joined Oct 9, 2013
Lol 9.5 Farads , too dangerous for you bro to play with these , i could have been killed by only a 0.99 uF one.

First make a tester for small value capacitors , if you can design that then am sure you can design a tester for bigger ones ;D


Joined Feb 11, 2008
Agreed! Probably pasted to X number of forums too, to see if he can catch a fish that bites and does his work for him.

Thread Starter


Joined Dec 19, 2013
Actually this design is my original work not copied from anywere, I am seeing that instead of help am getting comments on URGENT.
You may google it to verify.


Joined Nov 23, 2012
Our problem is, all if these specifications came from somewhere but you do not even indicate any capabilities or motivation to design something that can make this measurement.

Usually, someone with a self-designed project does not have any cause for an URGENT label, I would like to know why you have one.

Usually, someone with a self-designed problem has bothered to think of a solution so the question posed here is usually, "which is a better path forward, A or B? I am leaning towards A because..."

Usually, someone with so many specifications either skipped class, forgot to start his semester project near the beginning of the semester or, they lied on their résumé and are about to get fired.

If you did create these specifications, we will need a bit more input on what direction you would like to go with this. Then I think we can help with the details as you ask.
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