ANCHOR WINDLASS CONTROL
Install an electric anchor windlass. Another common failure point is the control system. In some simple systems a footswitch is connected directly in the positive power supply cable to the motor. Footswitches, especially the cheap ones, are notorious for filling with water, and in this case either a partial short circuit develops, or the main contacts and return spring corrodes.
Short circuits can result in a brief uncontrolled operation of the motor and a severely burnt out switch, so always isolate the circuit when not it is not in use. This is an essential check point on a boat that has been sitting a long time. In a single direction solenoid operated system the footswitch in a control circuit is used to operate a heavy-duty solenoid located below decks, which closes the main power supply to the motor.
The same arrangements are used for reversible systems, where a control box consisting of two or four solenoids which are used for reversal of the motor for both hoist and lower. These systems use two foot switches, and some systems also have remote panels for control. Never operate both foot switches together, and many manufacturers specify only the hoist foot control be fitted, with some incorporating protection.
Some boats have a pneumatic deck footswitch to overcome the problems of electric ones. These units consist of a PVC tube from the switch to the control solenoid box, and air pressure from the switch operates a micro-switch. There have been several instances of spontaneous start up or shut off failures in extreme heat conditions, in one case causing serious injuries. The problems are caused by pressure build-up in the air system in high heat conditions.
Earlier units were the most prone to the problems and major suppliers have already incorporated a safety air bleed to avoid the problem. There are correct depressurizing procedures when installing switches, so follow them carefully. Chain counters and controllers are now commonplace and some have controllers that enable programmed anchor control for precise rode lengths in or out, and automatic slow down when approaching the stem-head fitting. The display also shows the actual chain paid out. The system connects to the solenoid control system for directional commands, and has a simple power input. Like all control systems the connections must be secure
So many times I have witnessed people using them incorrectly and doing serious damage to them. Typical anchor retrieval speeds are around 30ft/minute at around 200lb loading, and higher loads will cause a slower anchor retrieval rate. Windlasses do not have a constant load during anchor recovery, but have a varying load according to the various phases of anchor recovery.
When operating your machine observe the following practices.
The first phase involves slowly motoring up over the anchor so the recovery rate will be at a maximum speed. This removes chain tension and makes recovery quicker and less load on the motor. The engine alternator supplies part of the motor load and keeps the motor from impressing a large voltage surge on the electrical system, and more importantly keeps the voltage from dropping too low. The anchor-windlass should never be used without motoring, the voltage drop can be severe so that a drop in power occurs after only a few minutes. If the anchor becomes fouled take the load on the chain-stopper and use the boat to break it loose and then resume retrieval.
The load will steadily increase as the tension increases towards the anchor breakout point. At the breakout point maximum current will be drawn for a brief period, and this current peak may be as high as 2-3 times the rated current. Once the anchor has broken out, the load drops as the windlass hauls the anchor vertically back to the boat. If you are having a problem with anchor retrieval, do not continue to load the windlass to stall conditions without stopping every few minutes, and allowing the motor to cool down. The motor may overheat due to the lower voltage causing damage or even burnout.
Most manufacturers publish performance curves and they illustrate the effect load has on power consumption and the subsequent reductions in hauling speeds. A point can be reached where the motor will overload and stall. The higher the load the windlass is operated at the shorter the operation time allowed on the motor as the higher currents overheat the windings and can burn them out. Motors have a duty cycle and operating at full rated load means a shorter available operating time.
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