Bow Thruster - Timer Switch Project

[Alex_Blackwood]

Seems strange no output rating for DC.
The Sidepower control unit has an internal fuse of 1A so I assume the control circuit is not much of a drain through the relay.

With a 3 amp ac rating I would expect the dc rating to be in the region of milli amps. The arcing from dc will be quite sever compared to ac you may end up with welded or burned out contacts in the future.

 

[Talulah]

With a 3 amp ac rating I would expect the dc rating to be in the region of milli amps. The arcing from dc will be quite sever compared to ac you may end up with welded or burned out contacts in the future.

Many thanks. I have no idea so will report back if I get problems. I'm tempted to put an ammeter in and see what the current is.

 

[Ridax]

I don't anticipate any problems in this regard. It is when the timer relay do the switch that it is sensitive for DC current load. In most cases when the timer relay switch, there is no current at all through the relay and only if it switch on/off while you press any of the control buttons it is doing a switch with current, and how often does that really happen?

 

[Talulah]

I don't anticipate any problems in this regard. It is when the timer relay do the switch that it is sensitive for DC current load. In most cases when the timer relay switch, there is no current at all through the relay and only if it switch on/off while you press any of the control buttons it is doing a switch with current, and how often does that really happen?

Phew. Sigh of relief.

 

[heartdoc]

Bow thruster switch

I have a Max-Power ct80 2003. The unit works only to the starboard side. The switch for the port thruster is intermittent and needs to be replaced. Any idea of where to purchase one or how to make a replacement?

 

[Talulah]

I have a Max-Power ct80 2003. The unit works only to the starboard side. The switch for the port thruster is intermittent and needs to be replaced. Any idea of where to purchase one or how to make a replacement?

Firstly, are you sure it's the switch?
It could be:
1. Control Panel
2. Control Box
3. Thruster solenoids
4. Brushes

To check at the thruster end remove the Solenoid Cover.
Apply +12V to where brown wire connects to solenoid. Thruster should operate one way.
Apply +12V to where blue wire connects to solenoid. Thruster should operate other way.

To check control box you could just swap the brown and the blue wires over on the connector.
To check the switches swap the switches over so port is starboard and vice versa.

You don't say what switches you have. I had a dodgy foot switch and took it apart replacing the actual switch inside with a foot switch from Maplin
http://www.maplin.co.uk/momentary-action-foot-switch-35033
I cut out an aluminium circle. Mounted the switch on the center of the new plate and fitted it to the round foot switch. Sealed it up with silicon. No problems since.

 

[nigelmercier]

Firstly, are you sure it's the switch?
It could be:
1. Control Panel
2. Control Box
3. Thruster solenoids
4. Brushes

5. The connections in the wires between the control panel and the device (been there, done that ...)

 

[Talulah]

Here are the foot switches.

 

[rogerthebodger]

My switches are in a very similar position but a little aft and closer to the centre of the boat. Mine are the vetus type that have flip up covers that cause the buttons to be recessed when the cover is down but protrude when the cover is up

 

[Alex_Blackwood]

I don't anticipate any problems in this regard. It is when the timer relay do the switch that it is sensitive for DC current load. In most cases when the timer relay switch, there is no current at all through the relay and only if it switch on/off while you press any of the control buttons it is doing a switch with current, and how often does that really happen?

Fully concur with what you say. However I would still like to know that the relay would handle the dc current if de-energised with the control circuit operated.

 

[Talulah]

Fully concur with what you say. However I would still like to know that the relay would handle the dc current if de-energised with the control circuit operated.

At £37 for the relay I hope nobody tries putting it to the test. Can't really happen if the helmsman is turning the control switch on/off. It would be like trying to play twister.
However, I could see it happening (although very unlikely) if the helmsman had his foot on the switch, no response and then asked a crew member to turn it on whilst still having a foot on the switch.
Cannot imagine the situation where the circuit would get de-energised whilst the control circuit operated.
The foot switches in the picture are actually quite substantial things. They each have a large solenoid as part of the switch mounted underneath. In the original design these solenoids were for supplying the main power to the thruster motor.
I don't thing the solenoids were ever used. As previously mentioned I have already repaired the switches inside using Maplin foot switches. These work well. I can't replace the units with the 'Vetus/Lewmar' type as the switch hardware stands proud. The whole switch unit is mounted to the cockpit floor base with the solenoids protruding through the cockpit sole in to the engine bay below. The hardware is such that the switch element is raised up to protrude through the teak grill.
For the Vetus/Lewmar switches to physically work a platform would have to be made to sit them on. This platform would also have to cover the holes in the cockpit floor.

 

[nigelmercier]

Here are the foot switches...

I'd hate that, I don't stand there in reverse.

 

[Alex_Blackwood]

At £37 for the relay I hope nobody tries putting it to the test. Can't really happen if the helmsman is turning the control switch on/off. It would be like trying to play twister.
However, I could see it happening (although very unlikely) if the helmsman had his foot on the switch, no response and then asked a crew member to turn it on whilst still having a foot on the switch.
Cannot imagine the situation where the circuit would get de-energised whilst the control circuit operated.

Sorry thought it was a timer. Does it not switch off after a set time? The thruster could be running when this happens? Have I got the wrong end of the stick?

 

[Talulah]

Sorry thought it was a timer. Does it not switch off after a set time? The thruster could be running when this happens? Have I got the wrong end of the stick?

Nope. You're right. My mistake. It could time out whilst the control circuit was active.

 

[heartdoc]

Definitely the switch. The switch is on the dash. on off with a toggle switch then starboard and port individual switches. I jumped the port switch with alligator clamps and the thruster worked beautifully. I'm told the switch is no longer produced. I am looking for another switch 2003 vintage. I may have to make make my own.