Electronic Test ESS TFX 5318 Powerstat Type 116 Hevi-Duty Transformer For Parts

Electronic Test ESS TFX 5318 Powerstat Type 116 Hevi-Duty Transformer For Parts

The Electronic Test ESS TFX 5318 is a self-contained AC power distribution and control unit combining a Superior Electric Powerstat Type 116 variable autotransformer (variac) with a Hevi-Duty control circuit transformer and a front-panel Simpson AC voltmeter, all wired into a heavy aluminum benchtop enclosure. The front panel provides three banks of numbered terminal strips (Units 1-5, 6-10, and 11-15), banana jack output test points, and a fuse-blown indicator lamp. A substantial multi-conductor wiring harness with military-style circular connectors exits the top of the cabinet, suggesting this unit was custom-built or integrated for a specific industrial test or power distribution application.

Specifications & What's Included

• Model: Electronic Test ESS TFX 5318
• Variac: Superior Electric Powerstat Type 116
• Variac Manufacturer: The Superior Electric Company, Bristol, Connecticut
• Internal Transformer: Hevi-Duty Electric Co., Milwaukee, Wisconsin
• Hevi-Duty Type: SIO Control Circuit Transformer
• Hevi-Duty Cycles Number: D41285
• KVA Rating: 0.750 KVA
• Frequency: 60 Hz
• Primary Voltage: 220/440V
• Secondary Voltage: 110V
• Phase: Single Phase
• Temperature Rise: 55°C
• Polarity: Additive
• Panel Voltmeter: Simpson, 0-500 AC Volts range
• Calibration Status: "Calibration Not Required" label affixed to front panel
• Terminal Distribution: 3 terminal strip banks — Units 1-5, Units 6-10, Units 11-15 (15 positions total)
• Output Test Points: Red and black banana jacks on front panel
• Fuse Status Indicator: Illuminated fuse-blown lamp on front panel
• Power Switch: Toggle-style switch on side panel
• Wiring Harness: Included — multi-conductor orange and green harness with multiple military-style circular multi-pin connectors
• Enclosure: Heavy aluminum cabinet with carry handle on front
• Form Factor: Benchtop enclosed cabinet
• Country of Manufacture: United States

Applications

Powerstat variacs from Superior Electric have long been standard components in laboratory and industrial power control applications, providing smooth variable AC voltage output from zero to line voltage (and slightly above). Combined with a Hevi-Duty step-down isolation transformer, a unit like this would have served as a custom power conditioning and distribution panel — delivering controlled, metered AC voltage to multiple test stations or equipment under test simultaneously through the numbered terminal banks. The military-style circular connectors and numbered unit distribution blocks suggest this assembly was purpose-built for a specific test bench, production test fixture, or industrial process requiring metered and distributed AC power to 15 discrete outputs. Hevi-Duty control circuit transformers were widely used from the mid-20th century onward in industrial control panels, machine tool circuits, and test equipment — their designs are straightforward and long-lived, making internal components potentially useful for repair or custom builds. This combination of a Powerstat variac, a step-down transformer, and a distribution panel in a single enclosure is characteristic of mid-20th-century custom industrial test equipment construction.