Simpson’s Portable and Switchboard shunts enable a panel meter to indicate higher DC currents than can be provided with a self-contained internal shunt. A typical shunt installation in series with the load and source is shown in the application section. These shunts can be used with either digital or analog meters. Most digital DC millivolt meters that Simpson manufactures can be scaled to display the actual current. Simpson can custom design any dial for the analog meters you require. Simpson manufactures two types of external shunts: Portable and Switchboard shunts.
Portable shunts are mounted in a phenolic base. This base allows the shunt to be easily installed in many locations. Portable shunts come in a 50 millivolt drop and a 100 millivolt drop. The most commonly used is the 50 millivolt
unit.
Switchboard shunts mount directly onto a buss bar and have a 50 millivolt drop. They have the same quality construction as a portable shunt, but without the phenolic base. Leads for these shunts are 5 feet long and are rated at 0.065 ohms resistance. Shunts with a 100 amp rating and below can be certified to NIST standards.