Harsh Duty® Generators

Harsh Duty® Generator

10KW TO 800KW, 60HZ AND 50HZ

These rugged units are built to withstand the most punishing environments – from hot, arid, dusty mining operations to humid, salt-laden sea air. With reinforced windings, fully encapsulated exciter stators and heavy-duty rectifier assemblies, Marathon’s Harsh-Duty family of alternators deliver low-maintenance reliability.

HARSH DUTY APPLICATIONS DEMAND HARSH DUTY GENERATORS

HARSH DUTY EXCITER

The ultimate in HARSH DUTY exciter stator construction. Coils are toroidally wrapped in fiberglass tape, fully encapsulating the winding and jumper sleeve ends. All coil to coil jumpers are fully sleeved. The windings are then fully submerged to ensure they are completely encased in 100% solid varnish. Finally, the complete exciter stator is coated with a two-component, anti-tracking top coat finish varnish for maximum protection in harsh and high moisture applications.

REINFORCED MAIN STATOR WINDINGS

Main stator windings receive multiple dip & bake cycles using 100% solid varnish. The main stator is then coated with a two-component, anti-tracking top coat finish varnish for maximum protection in harsh, high moisture, salt-laden marine applications.

HEAVY DUTY RECTIFIER ASSEMBLY

Harsh Duty generators often see harsh electrical applications including paralleling Make-Before-Break-Transfers, large motor-starting loads and highly non-linear loads. Marathon® Generator's heavy duty rectifier assemblies are designed to handle extreme voltage transient surges and over-current situations with diodes selected with ratings of 300% beyond worst case design requirements. Diodes are hermetically sealed, welded case stud type for maximum environmental protection.

Selenium surge suppressors are standard on models 360 frame size and larger. Selenium suppressors have self-healing characteristics and heat-sink capacity to handle up to 40x more power than a Metal Oxide Varistor (MOV) to better protect diodes during extreme loading conditions.

PMG EXCITATION SUPPORT SYSTEMS - OPTIONAL

When PMG excitation support is required, HARSH DUTY generators can be supplied with one of two PMG-ready voltage regulators. The proven Digital Voltage Regulator (DVR) provides ¼% voltage regulation utilizing the isolated PMG power supplier to assure maximum motor starting capacity and reliable voltage output independent of the load on the generator. The DVR also offers 14 different protective features, many customizable to your specific application and 300% short-circuit support to ensure long, reliable service life. The PM500 provides advanced voltage regulation and generator protection in a robust, analog package. With ¼% voltage regulation, the PM500 provides superior, full-wave dynamic performance, maximum motor starting capability, 300% short circuit support and six different protective features in an easy-to-use analog control package.

HARSH DUTY INSULATION - WHEN FAILURE IS NOT AN OPTION

Standard insulation systems are designed for operation in clean and dry environments. Most industrial environments include high levels of moisture, dust, sand, grit or other air-borne contaminates in the ambient conditions. These harsh industrial conditions may drastically reduce the service life of a standard insulation system.