Ripple Control Systems

Ripple control systems are a form of signalling system that superimposes an audible frequency signal over top of the standard 50Hz/60Hz mains power. It is primarily used to remotely switch street lighting, change dual-tariff meters between a high/low rate, cyclicly switch water heaters and air conditioners during peak usage times as a form of demand-side load management, and disconnect loads in capacity emergencies to prevent a complete failure. Ripple control has been in use since at least the 1920s and was originally based on completely electromechanical transmitters and receivers. The signal itself is a sine wave generated either by a motor-generator set or solid state methods, it is commonly around 1050Hz however modern systems have been moving to much lower frequencies. There are several different protocols that define how the signal is pulsed on/off to signal which receivers should operate in response to it. The transmissions can often be heard in transformers or motors and can cause some LED lighting to flicker whenever it is present, especially when power supply circuits with minimal filtering are used.

Ever since I first learned about them early in 2017, I have been very interested in ripple control systems and really wanted to learn how they work. Ripple control is quite common in Australia, New Zealand, and other countries, but it does not appear to be very common inside the US, which has made it difficult for me to learn about them. This section of the website is going to be dedicated to document my knowledge and findings on ripple control in the hopes that it will be useful to someone else in the future. I will be including pictures of the real receivers I have obtained, information on transmitters, coupling methods, transmission protocols, and documenting the custom transmitters/receivers that I have built on a small scale.