This page presents a test of a Common Capacitor Switch Machine Power Supply circuit. The circuit is uses two capacitors and a toggle switch to control single coil type switch machines such as Kato and Rapido machines.
The purpose of the test was to determine the limitations of the type of circuit.
This test measure the energy transferred between charged and uncharged capacitors with out a load or a source of additional charging.
The circuit allows four values of C1 to charge to full voltage but cuts off the charging when the fixed value of C2 is charged from C1.
Because the voltages in the system are squared in the calculations the rate of energy loss and transfer are not linear. C2 does not gain as much energy as C1 has lost.
The results of the test indicate that the switch machine will pass 1.8 times less energy when thrown from Reverse to Normal than it will pass when thrown from Normal to Reverse.
To counter the difference in energy transfer in the system above, the circuits on this page were developed.
This new circuit uses a power supply that is capable of supplying most of the current needed for the switch nmachine as well as large capacitor. There is as little restriction as possible on how quickly C@ can be charged to maximum voltage.
The explanations for the circuits on these pages cannot hope to cover every situation on every layout. For this reason be prepared to do some experimenting to get the results you want. This is especially true of circuits such as the "Across Track Infrared Detection" circuits and any other circuit that relies on other than direct electronic inputs, such as switches.
If you use any of these circuit ideas, ask your parts supplier for a copy of the manufacturers data sheets for any components that you have not used before. These sheets contain a wealth of data and circuit design information that no electronic or print article could approach and will save time and perhaps damage to the components themselves. These data sheets can often be found on the web site of the device manufacturers.
Although the circuits are functional the pages are not meant to be full descriptions of each circuit but rather as guides for adapting them for use by others. If you have any questions or comments please send them to the email address on the Circuit Index page.
12 March, 2018