A spark gap circuit includes a circuit board. The spark gap circuit also includes an input configured to connect to the circuit board and to receive signals. The spark gap circuit also includes a spark gap configured to connect to the circuit board and the input. The spark gap circuit also includes an output configured to connect to the spark gap. The spark gap is configured to cause a return loss between the input and the output to be within a first predetermined range. The spark gap is configured to cause a parasitic capacitance between the input and the output to be within a second predetermined range.

A spark gap circuit includes a circuit board. The spark gap circuit also includes an input configured to connect to the circuit board and to receive signals. The spark gap circuit also includes a spark gap configured to connect to the circuit board and the input. The spark gap circuit also includes an output configured to connect to the spark gap. The spark gap is configured to cause a return loss between the input and the output to be within a first predetermined range. The spark gap is configured to cause a parasitic capacitance between the input and the output to be within a second predetermined range.

A spacing-assured gas discharge tube assembly is installed on a printed circuit board, which may be part of a motor controller. The discharge tube assembly includes a tube body and an electrostatic spacing shield disposed at least partially around the tube body. The shield is configured to prevent close physical proximity of adjacent structures having electrostatic fields that may alter the breakdown voltage of the tube body.

A spark gap circuit includes a circuit board. The spark gap circuit also includes an input configured to connect to the circuit board and to receive signals. The spark gap circuit also includes a spark gap configured to connect to the circuit board and the input. The spark gap circuit also includes an output configured to connect to the spark gap. The spark gap is configured to cause a return loss between the input and the output to be within a first predetermined range. The spark gap is configured to cause a parasitic capacitance between the input and the output to be within a second predetermined range.

A spark gap circuit includes a circuit board. The spark gap circuit also includes an input configured to connect to the circuit board and to receive signals. The spark gap circuit also includes a spark gap configured to connect to the circuit board and the input. The spark gap circuit also includes an output configured to connect to the spark gap. The spark gap is configured to cause a return loss between the input and the output to be within a first predetermined range. The spark gap is configured to cause a parasitic capacitance between the input and the output to be within a second predetermined range.

Provided in the present utility model is a flameproof surge protector, including: a surge protector main body, a flameproof enclosure, a flameproof stopper plug, and a flameproof cable gland. One end of the flameproof enclosure is connected to the flameproof stopper plug, and the other end thereof is connected to the flameproof cable gland. The surge protector main body has an elongated shape and is disposed inside the flameproof enclosure, and a cable is drawn out of the surge protector main body by means of the flameproof cable gland. The flameproof surge protector provided by the present utility model has a simple structure and small size, can be used easily and installed inside an explosion-proof lamp, further protects a circuit inside the lamp, prevents the circuit from being damaged by surges, and is safe and reliable.

Provided in the present utility model is a flameproof surge protector, including: a surge protector main body, a flameproof enclosure, a flameproof stopper plug, and a flameproof cable gland. One end of the flameproof enclosure is connected to the flameproof stopper plug, and the other end thereof is connected to the flameproof cable gland. The surge protector main body has an elongated shape and is disposed inside the flameproof enclosure, and a cable is drawn out of the surge protector main body by means of the flameproof cable gland. The flameproof surge protector provided by the present utility model has a simple structure and small size, can be used easily and installed inside an explosion-proof lamp, further protects a circuit inside the lamp, prevents the circuit from being damaged by surges, and is safe and reliable.

A spacing-assured gas discharge tube assembly is installed on a printed circuit board, which may be part of a motor controller. The discharge tube assembly includes a tube body and an electrostatic spacing shield disposed at least partially around the tube body. The shield is configured to prevent close physical proximity of adjacent structures having electrostatic fields that may alter the breakdown voltage of the tube body.

An ESD protective device is provided which can lower a discharge start voltage. In an ESD protective device 1, first and second discharge electrodes 3 and 4 are disposed in a substrate 2 in a spaced relation with a discharge gap G interposed therebetween, and a conductor 9 is arranged around the discharge gap G. The conductor 9 has a nonlinear sectional shape in a section of the substrate 2 extending in a direction interconnecting a first principal surface 2a and a second principal surface 2b of the substrate 2 and passing the discharge gap G.

An ESD protective device is provided which can lower a discharge start voltage. In an ESD protective device 1, first and second discharge electrodes 3 and 4 are disposed in a substrate 2 in a spaced relation with a discharge gap G interposed therebetween, and a conductor 9 is arranged around the discharge gap G. The conductor 9 has a nonlinear sectional shape in a section of the substrate 2 extending in a direction interconnecting a first principal surface 2a and a second principal surface 2b of the substrate 2 and passing the discharge gap G.