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Centrally located in Cincinnati,OH, the Crohm team has over 75 years of experience selling, designing and manufacturing resistors for any application.

CC Case Resistors

CROHM Series CC case resistors are frequently used for light duty braking of variable frequency drives, heating applications and various AC and DC load applications. The internal resistor is hermetically and electrically sealed from its aluminum case and includes high temperature leads to simplify installation. The compact size is ideal for applications with limited space constraints.

CW Wirewound Resistors

CROHM Series CW wirewound resistors are frequently used for light to medium duty braking of variable frequency drives, speed regulation, wye-delta starting, heating applications, elevator controls, high resistance neutral grounding and any type of AC or DC power circuit. CW resistors are available in resistance values ranging between 0.2 to 300 ohms and varying current ratings 1 to 35 amps continuous.

CE Edgewood Resistors

CROHM Series CE edgewound resistors are frequently used for medium to heavy duty braking of variable frequency drives, speed/torque regulation, crane applications, elevator/mining controls, neutral grounding and any type of AC or DC load application. CE edgewound resistors are available in multiple lengths with varying current rantings 12 to 100 amps continuous.

CG Grid and CH Ribbon Resistors

Crohm Series CG Grid and CH High-Current Resistors are the industry leader for quality construction and dependability. Our designs feature stainless elements, heavy gage stainless steel terminals installed on double insulated metal frames. All elements feature either off-set grids or continuous ribbons welded to form a continuous current path free of troublesome current carrying spacers. Only high temperature silicon bonded mica insulation is used during assembly insuring that the bank is ready for rugged service and performance.

Dynamic Braking Resistors

Standard units feature CW Wirewound or CE edgewound resistors installed in an indoor screened enclosure with a galvanized finish and connected together with all stainless-steel bus bars. The resistors are wired to a terminal block located in either a separate compartment from the resistors or near the bottom of larger size free standing enclosures. The resistors are wired using high temperature silicone or teflon coated wire and high temperature lugs. We offer many enclosure options to suit your application demands.

Neutral Grounding Systems

NGR’s are used to ground power systems by connecting a resistor between the power system’s neutral and ground. This lowers the prospective ground-fault current to a predetermined value. A properly designed neutral grounding resistor provides benefits over both ungrounded and solidly grounded systems. By adding a grounding resistor to the system, transient over-voltages do not occur, and neutral ground fault current can still flow, allowing it to be detected and measured. Also, because a resistor is used to ground the system, the very large and destructive ground-fault currents created by solidly grounded systems are limited and controlled.

High Resistance Grounding Systems

During normal power system operation there is no fault current flowing through the resistor or power system. When a ground fault occurs the high resistance ground system will limit the fault current to a level that will not significantly damage the power system and immediately send an alarm signal to the user. The user can then activate a current pulse from the control interface that constantly cycles back-and-forth between a set current magnitude and zero. This allows the user to quickly trace and find the fault by using a hand held ammeter to follow the pulsing current to the ground point.

HR Resistance Grounding Picture

Trapp Industrial Sales Engineers have the experience and the training to help you with all of your Crohm product line applications.

Please visit the “Meet our Reps” page to find your local contact.