Welcome to Sankosha
For over 75 years, we have developed and manufactured the Ceramic Gas Tube Surge Arrester (Gas Discharge Tube or GDT).
Sankosha gas tube arresters protect personnel, equipment and circuitry from abnormally high voltages caused by
lightning or electrical transients. Our surge protection devices have well defined surge-limiting characteristics
enabling them to spark over (or breakdown) when the abnormal voltage on a line reaches a specific level. When sparkover
occurs in the GDT, the surge is redirected to earth. Sankosha’s gas tube arrestors are known for their quality.
Throughout the world, products from our factories provide protection for equipment and personnel. Sankosha has been
selling gas tube arresters in the U.S. since the seventies and Sankosha U.S.A., Inc., the company’s 100% owned subsidiary,
was established in 1987 to better service the growing market in the Americas. Different applications require
different surge suppressors and Sankosha provides gas tubes to meet every need. Consumer electronics, modems,
satellite, computer, CATV/Broadband, industrial, and telecom circuit protection are just a few areas that utilize
our gas discharge tubes. Sankosha’s gas discharge tubes are extremely durable and provide the industry’s best
impulse life specifications. They feature high surge ratings with very low capacitance and provide excellent
response to fast rising transients. Sankosha gas discharge tubes are available in axial leaded, radial leaded,
surface mount, and special packages. High voltage gas tube models like the Y08SV-312B are designed for power supply
applications where HiPot testing is required, and we also manufacture very small gas tube arrester models for surface
mount applications where real estate is at a premium. Sankosha’s GDT’s come in both two and three electrode
configurations. Discharge voltages from 75V to 6000V are available.
In the 1970’s, Sankosha developed SAN-EARTH, the original conductive concrete groundbed. SAN-EARTH M5C is a
fine powder used to build highly effective environmentally safe permanent grounding electrodes. SAN-EARTH M5C
is easily installed by spreading the dry powder in a strip over and around a conductor in a horizontal trench.
When the trench is filled in, SAN-EARTH M5C absorbs moisture from the surrounding soil and hardens to become
a conductive solid. The surface area of the electrode is dramatically increased resulting in significant
reductions in both resistance to ground and surge impedance. SAN-EARTH offers important advantages over
chemically charged electrodes and other ground enhancement materials. Placing 18 bags of SAN EARTH M5C results
in a resistance four times lower than would be achieved with four chemically charged ground rods and costs 65%
less. SAN-EARTH sets up much better than other similar products so less material is required. One bag is
enough to install a two-foot wide ten-foot long electrode. Other manufacturer specifications require three
times as much material. Independent testing has proven that corrosion is reduced by a factor of ten in
electrodes that are encased in SAN-EARTH. Safe, economical and permanent, SAN-EARTH is the best grounding
solution for both equipment performance and personnel safety.
In conjunction with the manufacture of SAN-EARTH, Sankosha also sells the most accurate grounding system Surge Impedance Tester on the market today. The best method for measuring the surge impedance of a ground system is to inject a sharp impulse current similar to an actual lightning impulse. Traditional methods for measuring the surge impedance of electric power transmission tower or other grounds use a low frequency AC bridge and the results obtained are very similar to the measured DC Ground Resistance. By applying a sharp impulse current between the tower leg and ground, and measuring the potential increase of the tower ground at a determined measuring time, this tester measures earth impedance easily and accurately and outputs the result on a digital display.
Sankosha U.S.A., Inc., 406 Amapola Avenue, Suite 135, Torrance, CA 90501
Toll Free: 888.711.2436 Ph: 310.320.1661 Fax: 310.618.6869 Email: sales@sankosha-usa.com