UGOR · Field Test Data · February 2019

Operating Force
Test Results

Measured input force on 230 kV gang-operated disconnect switches equipped with the UGOR. Tested at four substations using a calibrated digital crane scale with peak-hold function. Includes a direct side-by-side comparison against the Southern States HOGO operator on the same switch.

Bob White Substation — Head-to-Head

Same switch. Same day.
63% less force.

At Bob White substation, we were on-site while an original Southern States HOGO was being replaced with a new UGOR. We tested both operators on the same Southern States EV-2 230 kV switch before and after the swap, opening from fully closed to fully open each time.

Replaced
Southern States HOGO
29:1 gear ratio
40.3
lbs peak open force
vs
−63%
force
reduction
Installed
SSC UGOR
62:1 gear ratio
14.8
lbs peak open force

Switch: Southern States EV-2, 230 kV, 2,000A, year 2013. Both operators tested open-direction only from fully closed position, using the same Klau Model OCS-L digital crane scale. Hook-and-shackle attachment used for the Bob White test (custom fixture used at the three other sites).

Note on gear ratio selection: The 36:1 ratio is standard for the large majority of installations. The 62:1 is specified for unusually heavy or stiff switches where additional mechanical advantage is required. The Bob White switch used here was a 62:1 application.

Test Methodology

Calibrated instrument. Peak-hold. Real substations.

Instrument

Klau Model OCS-L digital crane scale. OIML Class 3 load cell, ± 0.2 lb accuracy across the range tested. Peak-hold function records the maximum force applied during each operation.

Fixture

A custom fixture was designed to attach the scale to the end of the UGOR crank arm at the same location as the operating handle. A handle on the opposite end allowed normal operating motion. Identical load-application geometry to field use.

Procedure

Scale set to pounds with peak-hold active. Switch operated to full open — peak recorded as the open value. Scale cleared. Switch operated to full closed — peak recorded as the closed value.

Calculated values

The 36:1 and 62:1 ratios share the same mechanical efficiency per the drive manufacturer. A measured result from one ratio can therefore be scaled to calculate the expected result for the other ratio at the same installation.

Klau Model OCS-L digital crane scale attached to the UGOR crank arm for force measurement testing at a substation
Klau OCS-L scale attached to UGOR crank arm via custom fixture — peak-hold active
UGOR Installation Results — Three Substations

Measured and calculated forces across gear ratios

Previously installed UGORs were tested at three substations. For each site, one ratio was directly measured and the other calculated from the shared-efficiency relationship.

Substation Switch Amp Year Ratio Max Open Max Close Source
Johnson Pascor VBPA 3,000A Est. 2000 36:1 17.4 lb 17.6 lb Measured
62:1 10.1 lb 10.2 lb Calculated
Proctor BBC TTR-6 2,000A 1985 62:1 9.0 lb 10.8 lb Measured
36:1 15.5 lb 18.6 lb Calculated
Laurelwood Pascor VBPA 2,000A 2015 62:1 16.6 lb * 11.6 lb Measured
36:1 29.1 lb * 20.3 lb Calculated
* Laurelwood open-direction force was substantially higher than the other sites. Attributed to switch setup at installation, not considered representative of typical performance.
230 kV gang-operated disconnect switch in closed position at substation
Johnson — Pascor VBPA, closed
230 kV gang-operated disconnect switch in open position showing blade travel
Switch in full open position
230 kV gang-operated disconnect switch at Proctor substation
Proctor — BBC TTR-6
Bob White Substation — Additional Detail

HOGO removed. UGOR installed. Tested both.

The Bob White test was an unplanned opportunity — we were on-site for the replacement, not a scheduled test program. The scale used was the same Klau OCS-L, but without the custom fixture. A hook was placed on the crank handle and a shackle used for grip. Both operators were tested open-direction only from fully closed. This makes the comparison valid as an apples-to-apples measurement under identical conditions.

Southern States HOGO — removed
OperatorSouthern States HOGO
Gear ratio29:1
Test directionOpen only
Peak open force40.3 lb
SSC UGOR — installed
OperatorSSC UGOR
Gear ratio62:1
Test directionOpen only
Peak open force14.8 lb

Switch: Southern States EV-2, 230 kV, 2,000A, 2013. Same switch, same day, same instrument. The UGOR runs at a higher gear ratio (62:1 vs. 29:1) and still delivers 63% lower peak force, reflecting both the ratio advantage and the efficiency of the sealed slew-ring drive.