GeoVISION™ Cable for Borehole Video Camera Systems GeoVISION Home
The goal of designing and manufacturing the best cable for a borehole camera system is to balance the eight relevant factors of cable engineering:
5. Protective covering and insulation
6. Resist absorption of chemicals
GeoVISION™ has designed its cable to specifically meet these criteria with the best balance of all these factors. John, MPI Marketing Director, is shown suspended by the GeoVISION™ cable. He is using a repelling rack and a seat harness to attach to the cable. The total weight of John and all the equipment is about 195 pounds. It took almost another 100 pounds to break this cable.
The GeoVISION™ cable will hold 200 pounds. It was upgraded from 160 pounds in 2006 when GeoVISION™ introduced its 2000 foot deep camera system. No GeoVISION™ cable has ever been broken in use since it was introduced in 1989. If the GeoVISION™ cable will hold John, our 175 pound Marketing Director, it will hold a two pound camera. We could make it stronger; however, that would add weight, bulk, and cost. Twenty years of experience says it is strong enough. A special clamp securely connects the camera to the cable above the electrical connector.
The GeoVISION™ cable weighs about 5 pounds for 325 feet (100 meters) of cable. The 1000 feet (300 meters) cable length weighs about 15 pounds. Since the cable is the heaviest single item in 1000 to 2000 foot systems, the modest cable weight means that GeoVISION™ systems are lightweight and can be picked up by one person. A lighter more compact cable means the winch is smaller and lighter. Portability is an important factor. GeoVISION™ systems can conveniently be moved by car or pick-up truck and shipped as luggage on an airline. Your back will appreciate our efforts to keep the weight down.
The GeoVISION™cable is a flat, three conductor cable that is intended to be space efficient. The flat shape allows it to be placed on the winch drum, with less unused space when compared to round and coaxial cable. The Deluxe winch holds 2000 feet and the Econo Heavy Duty holds 1000 feet of cable in smaller spaces than would be possible with a round cable. The GeoVISION™ flat cable allows for a smaller size winch and smaller size shipping container.
The three conductors provide more than adequate conductivity to power the LEDs, operate the camera, retrieve the video signal, and operate optional equipment such as the motorized pan and tilt. The center wire is 100 percent copper and the two side wires are copper clad steel. This design provides the best combination of strength and conductivity.
Protective Covering and Insulation
The polyethylene sheath provides an adequate protective covering and insulation. This protective insulation can withstand many years of heavy use in boreholes. Based on the experience of more than a thousand systems in service for many years, the GeoVISION™ cable represents the best balance of insulation versus weight and bulk.
Resist Absorption of Chemicals
The polyethylene sheath of the GeoVISION™ cable resist the absorption of chemicals and contaminates. The cable is less likely to transfer contaminates such as oil or gasoline to another well. It is recommended that if any contaminates have gotten on the cable surface, they be removed, preferably as the cable is being rewound onto the winch to avoid contamination of other wells.
May be Repaired and Spliced
The three conductor design allows the cable to be cut and spliced together to remove a damaged section of the cable. This and other repairs may be done in the field to expedite a job. This is a very rarely needed option; however, it can be a major cost saver in some time critical situations should the cable be damaged by accident.
The GeoVISION™ cable is a relatively small portion of the overall system cost. The overall good engineering and design of GeoVISION™ systems helps contain cable and system costs.
Overall Cable Evaluation
The GeoVISION™ cable achieves the best combination of these six factors for most users. Understanding how borehole camera systems are used helps us balance all these factors to provide the most cost effective borehole video camera cable.
The GeoVISION™ cable is a stock item at the MPI factory and customers can replace the cable on their winch. All GeoVISION™ cameras have threaded connectors that allow the camera to be detached from the cable, so that either the camera or cable can be interchanged, repaired or replaced.