GN BOXCAB (3 PHASE) ELECTRIC LOCOMOTIVE

The GN boxcab locomotives were the first electric locomotives purchased by the Great Northern Railway (GN) for use through the Cascade Tunnel. Four locomotives were supplied were built in February and March 1909 by the American Locomotive Company, and delivered in Pullman Green; they used electrical equipment from General Electric and weighed 115 tons (104 t) each.

They were three-phase electric locomotives with specifications calling for 1,000 hp (750 kW), but the actual output was substantially greater at 1,500 hp (1,100 kW) each, as described by the consultant engineer Cary T. Hutchinson. They had a B-B wheel arrangement. GN numbered them 5000–5003 and they were used until May 1927, after which all were scrapped.

Initially, three locomotives were coupled together and hauled trains at a constant speed of 15.7 mph (25.3 km/h), but when larger trains required four locomotives the motors were concatenated (cascade control), so that the speed was halved to 7.8 mph (12.6 km/h) to avoid overloading the power supply.

GN boxcab No. 5001.

(General Electric Company, Schenectady, New York, Public domain, via Wikimedia Commons)

Great Northern Boxcab (3-Phase) Overview

Type and origin
Power type: Electric
Builder: GE and ALCO
Serial number
Alco: 45289, 45286–45288
GE: 2895, 2892–2894
Build date: February–March 1909
Specifications
Configuration:
• AAR B-B
• UIC Bo′Bo′
Gauge: 4 ft 8+1⁄2 in (1,435 mm) standard gauge
Wheel diameter: 60 in (1.5 m)
Length: 44 ft 2 in (13.46 m)
Width: 10 ft 0 in (3.05 m)
Locomotive weight: 230,000 lb (100,000 kg; 100 t)
Electric systems: 6.6 kV, 25 Hz AC (3-Phase)
Current pickup: Pantograph
Traction motors: 4 × GE-1506
Gear ratio: 19/81
Performance figures
Maximum speed: 15 mph (24 km/h)
Power output: 1,500 hp (1,100 kW)
Tractive effort:
• Starting 57,500 lbf (256 kN) at 25% adhesion
• 1 hour 38,000 lbf (170 kN)
• Continuous 34,800 lbf (155 kN)
Factor of adhesion: 25%
Career
Operator: Great Northern Railway
Number in class: 4
Numbers: 5000–5003
Delivered: 1909
Retired: May 1927
Disposition: All scrapped