1. 10.030 CABLEWAY GUIDANCE NOTE 2:
DRAFT SPECIFICATION
Approval Date: this is a guidance note only Version: 1
Purpose
The cable way is to be used for discharge measurements by current meters, in rivers.
Conditions and requirements
• The cable way shall be of such a design that it operates reliably and safely under
the prevailing environmental conditions.
• The cable way shall be bank operated.
• The cable way shall be easy to operate and maintain.
• The cable way shall be supplied with accessories as needed for effective
deployment.
• All critical materials on the cable way exterior shall be non-corrosive.
• The cable way shall have an expected technical lifetime of not less than 10 years.
• Operating and maintenance manuals, related to the type and model of the cable
way, shall be part of the delivery.
• A hand driven winch system to traverse the trolley (instrument carrier) and to lower
and hoist the current meter shall be provided at one of the towers on the
riverbanks.
• While winding, the cable shall be wound gradually guided from the one drum end to
the other and vice versa, to lay the windings tidily next to each other.
• The winch system shall have a distance and a depth counter, both re-settable.
• The suspension cable, shall have an incorporated insulated electrical conductor, to
connect the current meter to a pulse counter via a slip-ring set at the winch system.
• The suspension cable shall match the cup/propeller type current meters.
• If a propeller type flow meter is used then the suspension cable shall be torque
free.
• Instrument suspension cable shall disengage itself, in case drag load on it exceeds
2,500 Newton, due to either current on it or on attached debris etc.
• Construction and support are not part of this specification.
• It is recommended that the supplier be made responsible for all facets of the work,
i.e. design, supply, installation and commissioning and training.
• Optionally, and in addition to the hand driven system, a motor driven winch system
could be included. The motor could be an electrical motor or a diesel engine.
• If an electrical winch is specified, then a compatible power generator should be
included in the delivery.
• The winch motor shall be reliable both in starting and in control.
• The motor driven winch system shall have a manual override.
• The current meter shall be equipped with a bottom sensor below the current meter
body.
• Upon reaching and touching the bottom, the bottom sensor shall close a switch.
The switch closure shall generate an electrical signal over the measuring cable to
notify the observer, e.g. by an audible alarm and/or a signal light.
• The speed of the winch shall be reliably controllable for accurate positioning of the
interments.
Equipment Guidance Note: CABLEWAY Version 1 10.030-1/2

2. • After positioning and blocking the cables for measurements, none of the cables
may slip except when overloaded. In the latter case of an overload the built in
safety measures may be activated.
Specifications
The purchaser may execute his judicious discretion in the choice of configuration and
options.
river width •up to 100 m size 1
•up to 200 m size 2
river depth max. 20 m
flow velocity max. 5 m/s
mass of current meter up to 125 kg, including sinker weight
Winch motor
electrical 220 VAC ±25%, 47 to 53 Hz
temperature range 0 to 50 °C
housing splash waterproof
OR
diesel sufficient power
Remarks
The design for the cable way depends on the site specific conditions. The engineer in
charge shall finalise details for tower height, minimum admissible clearance between
peak water level and cable, bank where the winch shall be located, civil works etc, in
collaboration with the supplier.
Equipment Guidance Note: CABLEWAY Version 1 10.030-1/2