. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography Fig. 4 Measurement and Telemetry System It may be noted that this system is conserva- tive in that power is only taken during penetra- tion, retraction, and rotation of the vane or while a command is sent to the tower, and that during periods of torque measurements, no command currents exist on the ship to tower cable. Measurement and Telemetry System Torque Gage In its final version, the torque gage consists of a reduced section of the vane drive r
. Collected reprints / Atlantic Oceanographic and Meteorological Laboratories [and] Pacific Oceanographic Laboratories. Oceanography Fig. 4 Measurement and Telemetry System It may be noted that this system is conserva- tive in that power is only taken during penetra- tion, retraction, and rotation of the vane or while a command is sent to the tower, and that during periods of torque measurements, no command currents exist on the ship to tower cable. Measurement and Telemetry System Torque Gage In its final version, the torque gage consists of a reduced section of the vane drive rod which is gaged with bonded electrical resistance strain gages. This section is located just above the vane attachment point. Four gages are located to measure the tensile and compressive strains in the cylindrical element which resulted from applied torsion. The gages are connected to cancel strains due to both bending moments and axial loads. Gages were carefully applied to avoid entrapped air or other bubbles under the gage. Waterproof- ing consisted of layers of wax, RTV silastic, and a commercial sealant called "; Lead wires were stripped of all insulation and directly embedded in the waterproofing to seal the gage. Lead cable was located in a 7 mm slot cut in the square vane rod to the upper end of the rod where the cable festooned to the instrument housing. The cable was placed in this slot to protect it from the force of the soil during rotation and to permit passage through a square-holed rotary drive plate which turns the vane. The gaged and waterproofed section also pre- served the same drive rod geometry to protect the gaging during penetration and retraction. Waterproofing of electrical strain gages is always a problem and the hydrostatic pressures encountered at design depths made the excel- lence of waterproofing of prime importance. Electrical strain gages produce only a small resistance change from elongation of its conduc- tors. Because
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