Power feed from genset for running electric raw water pump.

[Simi 60]

On an Australian vessel.

In another post I had pump problems on the genset.

https://www.cruisersforum.com/forums...ng-229948.html

As it requires blood letting and total removal to change the impeller and a new impeller this time never got it pumping again anyway I have decided to go 240v electric pump , which I have done for a greatly improved result.

I threatened to do this back in 2018
https://www.cruisersforum.com/forums...ch-204159.html

My question for those with electrical knowledge is about connecting the electric pump to the 240v feed so as to have auto pump on at startup and auto pump off at stop Vs the manual approach I currently use.
Below is a pic of the wiring on top of the genset.

I have an outdoor type 240v socket I can mount on the other side of the sound shield, I have the correct sized wiring and the correct sized terminals.
Can I wire the plug straight in to get a working 240v socket only usable when the genset is running?

Before you say it.....
We are out cruising.
No marina nearby and no electrician to pay.

[Simi 60]

No comments?

Figure I'll cut the plug off of this, wire in direct and surface mount it to the sound enclosure.
That gives me two 15amp plugs that will accept 10amp and an RCD/ safety switch built in.

[Wotname]

OK, I get that you don't have access to a qualified electrician so take the following with the disclaimer that I am also not a mains qualified electrician but I have been working with electricity professionally for 50 years (low to high levels of DC and low and medium levels of AC).

First you need to know if your genset has the earth wire connected to the AC neutral (the one you marked as - ). Some do and some don't.

If it isn't, than the RCD / safety switch of the outlet shown will do nothing!!!

If it is, then the protection offered by the shown outlet will depend on it's IEC number which presumably is shown on the device somewhere. In your situation, IEC 61009 is good while IEC 61008 is not good.

IEC 61009 provides both residual current and overload protection where as IEC 61008 only provides residual current protection with no overload protection.

Note, to repeat, neither of them will provide any residual current protection if the earth and neutral are isolated at the genset.

At a minium, you should have (no, you need) overload protection i.e. a fuse or circuit breaker as near as possible to the source (i.e. genset).

Please come back with questions if the above is unclear, we don't want to hear about another boat fire.

Also watch this for a basic primer on RCDs.
https://www.kerfoot.com.au/news/how-does-an-rcd-work/

[Simi 60]

Thanks for the response.

First you need to know if your genset has the earth wire connected to the AC neutral (the one you marked as - ). Some do and some don't.

Got me there and why I havent dove in as yet.
I assumed the big black was neg and the green/yellow was ground/ earth which, is also connected to the neg in that pic

If it is, then the protection offered by the shown outlet will depend on it's IEC number which presumably is shown on the device somewhere. In your situation, IEC 61009 is good while IEC 61008 is not good.

IEC 61009 provides both residual current and overload protection where as IEC 61008 only provides residual current protection with no overload protection.

The one I got specifically says...

Portable Double RCD Power Outlet (2 outlets/socket)
240v, 15 Amp Plug
All products are Australian and New Zealand approved - SAA Approved
E-mail for any further inquiries or for bulk order
MCB/RCD Protection
Brand new in retail box
https://www.ebay.com.au/itm/Builders...c984%7Ciid%3A1

Google says...

RCD means Residual Current Device and MCB means Multiple Circuit Breaker. ... An MCB will save your home from electrical fires by ensuring that the wires are not overheating and that there is no overload on the various electric circuits. You need to ensure that you have both of them in your house

So at least I have that bit covered

[Wotname]

Originally Posted by Simi 60

......
The one I got specifically says...


Google says...


So at least I have that bit covered

Probably (most likely) but the devil is always in the detail so as a belt and braces approach, can you post a picture of the RCD/MCB device on the side the outlet or at least the model number of the breaker assuming it is on the outside...

[Wotname]

Originally Posted by Simi 60

Thanks for the response.

Got me there and why I havent dove in as yet.
I assumed the big black was neg and the green/yellow was ground/ earth which, is also connected to the neg in that pic

........

Thanks, I missed that in my first viewing

I was concentrating at looking at the top row of three terminals. So yes, the neutral and ground are connected so the RCD/MCB should function as intended.

FWIW, regarding terminology, there is no +ve and -ve wires when talking AC. There is an ACTIVE (sometimes called HOT) and a NEUTRAL wire plus the GROUND/EARTH wire. In the mains supply, the NEUTRAL is always connected to the GROUND wire at the source. In a portable generator, this is often not the case and both wires are "floating" and you can touch either one of them (but not both at the same time) and feel nothing. In the mains supply, if you touch the ACTIVE and are standing on the ground / floor / ladder etc, you will know about it (or be dead).

If the NEUTRAL is wired correctly, you can touch it without noticing anything. If it has been wired incorrectly (as often happens even by qualified folk), it can be the same result as touching the ACTIVE.

[Wotname]

Supplementary question - what is the rated output of the genset?

IE can it support two 15 amps loads?

Put another way, is it greater than ~ 7.5 KVA. If not, only use one of the 15A outlets.

[Wotname]

Also FWIW (but not wishing to tell you how to suck eggs), the colours in the outlet cord should be:
Brown is ACTIVE
Blue is NEUTRAL
Green/yellow is GROUND

As the cord will be electrically unprotected until it is inside the outlet, keep it as short as possible and ideally provide it with some additional mechanical protection, i.e. conduit or even some water hose until you get the proper conduit.

I did say I like belts and braces .

[Simi 60]

Originally Posted by Wotname

Supplementary question - what is the rated output of the genset?

IE can it support two 15 amps loads?

Put another way, is it greater than ~ 7.5 KVA. If not, only use one of the 15A outlets.

It is a 7.5 kva 3 pot Kubota engined
Reality is the most it will ever have is the small electric water pump">raw water pump running from it.
240v power points are throughout the boat for other devices.

[Simi 60]

Originally Posted by Wotname

Probably (most likely) but the devil is always in the detail so as a belt and braces approach, can you post a picture of the RCD/MCB device on the side the outlet or at least the model number of the breaker assuming it is on the outside...

Have contacted the seller for further detail so most likely wont hear back until monday

Thanks again for your help thus far

[techmans]

Why run the essential pump over a plug and outlet that may accidentally be disconnected.( Vibration anyone? )
You would never know unless you had a loud alarm on the pump output.

Why not hard-wire the pump and using an inline fuse close to source over which you connect a loud, piercing alarm. If the fuse blows ( pump shorted out) the alarm will sound.Rig in a push button test circuit for the alarm to test on start-up.

[Squanderbucks]

Most likely you have a slide or rotary switch that selects between shore power, off, and gender power.
But power to the pump should not go through the main circuit panel as it will not be able to power the pump if switch is set to off position which you might like to do at startup before switching from one source to another.

I would get and setup a small separate breaker directly wired to AC Out at the genset. Dedicate the wires to a three prong plug that is mounted on or nearby the breaker.
That way no matter how your selector switch is set you can be assured the water will pump when AC power is coming out of the the unit.

[wrwakefield]

Our 10Kw generator uses a 110V AC March Pump, replacing the belt driven raw water impeller pump mounted on the engine.

It is direct wired to the generator output similar to what you are contemplating.

The March pump is low enough amperage that it doesn't affect the capacitor excited voltage regulation at start-up... [The Fisher-Panda manual warns against starting the gen with any AC loads for this reason.]

It has been working well this way for ~15 years or so...

In case this is helpful.

Best wishes with your project.

Cheers! Bill

[Simi 60]

Originally Posted by techmans

Why run the essential pump over a plug and outlet that may accidentally be disconnected.( Vibration anyone? ).

Because I want a couple of PowerPoint's in the ER that don't rely on inverter power.
Most items on the boat run on 240v, haven't had a plug drop out yet.

You would never know unless you had a loud alarm on the pump output.

Or had a loud temp alarm on exhaust elbow and auto temp shutdown.
Both of which it has.

Why not hard-wire the pump and using an inline fuse close to source over which you connect a loud, piercing alarm. If the fuse blows ( pump shorted out) the alarm will sound.Rig in a push button test circuit for the alarm to test on start-up

Reasons given above

[Simi 60]

Originally Posted by wrwakefield

Our 10Kw generator uses a 110V AC March Pump, replacing the belt driven raw water impeller pump mounted on the engine.

It is direct wired to the generator output similar to what you are contemplating.

The March pump is low enough amperage that it doesn't affect the capacitor excited voltage regulation at start-up... [The Fisher-Panda manual warns against starting the gen with any AC loads for this reason.]

It has been working well this way for ~15 years or so...

In case this is helpful.

Best wishes with your project.

Cheers! Bill

Pump I am using claims 35w @ full flow
If watt to amp calculators are correct it should be pulling less than an amp similar to a march pump