Periodically checking the condition and operation of circuit breakers is essential to keeping power systems safe. Knowing what to look for allows for proper selection of equipment and test procedures.

Making a device to test an RCD is easy; a resistor between hot and the protective ground circuit would do. [Callan] over-engineers. He used a 50 W resistor where 30 W would do under the worst ...

RS232 uses two-way transmissions and is common in low-end professional and consumer equipment. BCD Binary coded decimal (BCD) is a circuit code which represents decimal numbers in binary code. With ...