For Magneto Telephones
The SPRINT Kit assists in the safe, reliable and efficient performance of magneto telephones (to specification IRS TC 36) at critical railway locations. It provides the magneto telephone with:
- An efficient and independant solar based power supply with back-up;
- Surge protection for the communication line;
- Sensitive high impedance line ringer;
- Connection terminals and selection switch for spare magneto telephone.
Magneto telephones at many railway locations face three major hazards:
- Erratic mains based power supply, or batteries requiring frequent change;
- Damage from voltage surges, especially during monsoons.
- Ringer or generator malfunction.
The SPRINT Kit provides the following solutions:
- Solar based power supply with Lithium-Ion back-up as a reliable and consistent power source.
- The Solar power arrangement eliminates all contact with AC mains, thereby avoiding exposure to lightning and surges that spread through the power grid. Hence no surge protection is required for the power supply. Underground cables are nowadays used for communication lines. These have minimal exposure to lightning and power surges. Any rare spikes that still impact the line are shunted to ground by the SPRINT module.
- Breakdowns in magneto telephones over a period of time are mainly the sending or receiving of ring voltage. The SPRINT module has a built-in ringer circuit that serves as a parallel ringer for incoming rings even if they are very weak. For outgoing rings it will sound to indicate that proper call voltage has been sent by the telephone generator. If a fault in the ringing or generation of the magneto telephone becomes evident, a selector switch permits a spare connected magneto telephone to be deployed without delay.
A Bargraph illustrates supply from the solar panel. Faults such as dust accumulation, shadow, position shift, disconnection or theft of the panel can be deciphered easily.
Indicators for Battery Level and Battery Charge display the battery status
USB charging facility works from spare solar energy (after internal battery is topped up) to charge mobile phones that become useful in emergencies.
Sensitive ringing system of the SPRINT module works as a parallel ringer with a fraction of the insertion loss, to indicate incoming as well as outgoing calls. This enables magneto telephones with faulty ringer to remain in use. It also responds to calls from a magneto telephone having a weak generator or is at a great distance or there are many parallel telephones on the same line.
Second set of terminals with changeover switch permits a spare magneto telephone to be deployed without delay
Powering the Interface module is possible from any of three sources: 1) From solar panel that is part of the kit; 2) From a DC source of 7 to 36 V (instead of solar panel); 3) From a mains powered mobile charger (however, this will expose the Interface to surges that might arrive through the grid).