Shore Power Cord

[FlyNavyAir]

I need to replace the shore power cord on a 1991 Hatteras 52 CMY. I believe the current cord is original to the vessel and is very stiff and cracked. In fact, it is so stiff that it does not fully retract via the Glendinning Cablemaster (CM-7). I spoke with Glendenning rep and he said they can provide a new cable but they need to know if it is 3 wire or 4 wire. I have the 120/240V ships service system schematic that states "this is basically a 120/240V 3-wire distribution system." Just to be on the safe side I want to ask for assistance to confirm I should order a 3-wire shore power cord. Thanks in advance for your advice.

 

[Boatsb]

Look at the Glendinning connections. It will have either 3 or 4 wires on it.

 

[Glory]

I am sure it would be 4 wire if you have "240" volts.

 

[jmooney]

With an isolation transformer you only need 3 wire . Easier to handle and a smaller coil for the same length. You can measure the diameter to tell which cable you have , but removing the end and counting the wires is pretty foolproof.

 

[davidwigler]

Count the blades on the plug.

 

[Pascal]

Indeed if you have isolation transformers you don’t need Neutral and can use a 3 conductor cable (Red, black and Green)

Counting the blades on the plug isn’t going to help as most plugs have all 4 anyway. To be sure, look at the terminal block inside the boat by the Glendining.

Before ordering the cable from glendining, ask if the wires are tinned. I have had issues with non tinned shore power cables in the past (on a 70 footer with two 50 amp glendinings) I replaced the cable with tinned cable ordered by the foot from Ward Electric in FTL). Much cheaper too.

I recently replaced the 100 amp cable on the 84 footer I run, also with bulk cable from Ward. The original glendining cable had been nicked at some point and One of the conductor Corroded badly.

 

[captcrunch]

Had to replace an end recently on my 50amp 240v cable and it had 4 wires. Not sure if it helps

 

[racclarkson@gmail.com]

I bought 90' of 4-wire from Glendinning a couple of years back because they are close enough for me to pickup. The neutral on mine is not used. But since the boat came with 4-wire originally, I replaced it with same. As far as I know, Glendinning cords are not tinned. However, they will install the plug and seal it properly.

 

[Pascal]

The two cables that failed on me had damage away from the plug.

I discovered the problem on the 50 amp cable during a routine heat check, I run my hand over the whole thing under load. There was a significant hot spot about 20 feet from the plug even though there was no apparent cut or damage. The post mortem showed no corrosion on the un-tinned conductors close to the plug, it started about 10’ away and got worst peaking at the real hot spot

The 100 amp cord had a nearly invisible 1/2” cut in the usually unused portion stored in the bucket, about 15’ from that end. No idea how long it had been damaged, it had to have happened before I started running the boat. Now that one was a close call as it could have started a fire. I noticed the problem walking in the crew area smelling something close to burning. Again the 10 year old cable was untinned and too hot to touch.

Now I also check the unused portion of the cable on a regular basis.

I recently replaced the 50amp cord on my boat with tinned cable and new plugs. I will never use Un tinned cable. Ever.

 

[doc g]

If you have iso transformers you only need/want two conductors, but I am sure that two wire will not work in a Cablemaster, but still only wire the two "hots" in the plug......................Pat

 

[FlyNavyAir]

My thanks to all for the advice and assistance. I'm sure I'll be back soon with additional questions as I'm new to the power boat arena. 35+ years owning sailboats. Stay well!

 

[Pascal]

If you have iso transformers you only need/want two conductors, but I am sure that two wire will not work in a Cablemaster, but still only wire the two "hots" in the plug......................Pat

Just two be clear, you need the two lines/hot AND THE GROUND.