I like the idea from Happy.. to use a ESC to control the speed of the pump and thereby the discharge rate of the fire nozzle.

In the past I've linked a firepump to a small 10amp ESC so I can control the throw of water via separate channel. Much prefer that over the instant on/off variety

I couldn't agree more Dave RR👍
Cheers, Doug (RNiM)😁😎

I would personally put that pump on the shelf and buy a continuous pump to be controlled from the tx. “All problems are illusions of the mind.” “A problem well stated is a problem half solved.” Dave RR

Duncan.
It sounds as if you have made your decision re your plan.👍
We are all individuals thank goodness and have our own plans to suit our needs,it’s just nice that we can pick other fellow builders brains and mix and match.
Bill👍

I intend to switch it off manually after approximately 20 to 30 seconds - so not worried about having a timer. 😊 I'm just aiming to satisfy the requirements of the pump. Perhaps a bad decision on my part of the water pump I chose. It was just that the spec indicated it was self priming and suitable for a water monitors and I managed to resource one for £4+ less than other offerings of this particular pump. 😊

Hi Duncan,
What are the type and dimensions of your boat? Especially the draft.
I find it hard to believe that there's not enough draft to fit a small self-priming pump (such as I posted) below the waterline.
Otherwise you will have to devise a 30 sec / 2 minute timing circuit as indicated below.
Cheers, Doug😎

Lew,
"he will also need some sort of resettable timer."
Exactly👍 And a momentary push switch on the TX to trigger it.
Cheers, Doug 😎

Hi Lew, The reason for mentioning the 30second burst is that this is a restriction that was posted on the Caldercraft water pump that I have ordered. I chose this pump as it is self priming because I couldn't be certain that the inlet pipe would be below the waterline.

Doug,
I meant for a true switch to be one device. The unit in question is a circuit to function as remote switch, sort of an extension of the switch on the transmitter. Yes, in reality a relay performs the electrical function similar to a switch. Really doesn't matter much anyway (semantics?).
I'm a little puzzled by Duncan's question on "Has anybody had any experience of this switch for use on switching on a pump for a fire monitor with bursts of 30 seconds for the water jets."
The device (good for 20 amps) should work for any duration of time, not just 30 seconds. If he means to flip the transmitter switch and the monitor will automatically turn off after 30 seconds he will also need some sort of resettable timer.
Lew
Florida, USA

Hi Michael,
"DuncanP has a tread on "R/c switch for 6v-12v water pump for fire monitor"
Please keep your comments to this subject otherwise Duncans question will get lost"
Well said Michael, but I hope that neither you or Duncan have trodden on your RC switches or they might not work so well😁
Or is that akin to a foot-switch? 😂
Cheers, Doug 😎

Hi Lew,
"These are not really true switches, but relays."
How then do you define a 'true switch'?
Mechanical slide, toggle or push button?
Capacitive 'touch' switches (which have a transistor 'switch' behind them)?
Or RC switches, such as used in our models?
These use either FET switching transistors or, as in the case of the one Duncan posted a relay, as the output device.
The relay simply isolates the load voltage supply from the RC pulse decoder and relay driver transistor circuit supply, usually from the RC receiver. Thus allowing the unit to switch higher voltages and high current loads without overloading the receiver supply and causing burn outs within the receiver.
Happy switching folks😊☹️😊☹️😊
Cheers, Doug 😎

Hi Duncan,
First off; I would not pay that kind of mullah for a pump the only works in 30sec bursts and then need 2 minutes to get it's breath back!
(Or do you have a specific reason for wanting only 30second bursts of water? Be interested to hear what.)
Especially when there are cheaper alternatives which can run continuously; see link below to a 'standard' Graupner pump; used for years with no problems.
Or; windscreen washer pumps from scrapped cars are cheap and bear a striking resemblance to the Graupner product😉
Then you only need a simple on / off switch; such as Herman's servo driven micro-switch.
Or an RC switch such as in your original post. It is simply an ON/OFF switch using a relay to enable switching high current loads (max 20A). It does not appear to have any sort of timing function. I've not used that specific switch but various others that work the same way. There's nothing special about that switch.

Hope this helps,
Cheers, Doug😎

https://www.modelshopleeds.co.uk/catalog/product_info.php?products_id=24558

I used a similar switching devise for my Crashtender controlled via a single channel, mine was from Hobby King
PS
DuncanP has a tread on "R/c switch for 6v-12v water pump for fire monitor"
Please keep your comments to this subject otherwise Duncans question will get lost
https://hobbyking.com/en_us/turnigy-receiver-controlled-switch-1.html

Scratchbuilder there are 3 other threads running today all abt ultrasonic steam production. Did you build your own generator or buy from somewhere? I tried using an ultrasonic gen & disk off AMAZON but the 2 different versions were unreliable. I am currently experimenting with power resistors & a wick, trying for grey to black smoke using glycerine or baby oil thinner with alcohol. Not happy yet

Evening Rod.
I don’t want to break the water pump thread here,but!
The orange box is the water tank for the water based smoke/steam generator.
The copper fittings are 15mm water pipe and are offset so that a straight upright section fits up thru the flight deck into the bridge island and exits the funnel.
Works a treat.If you have a look in my boat harbour there are more pictures of the carrier HMS Victorious.
If I can help further let me know.
Regards Bill

Scratchbuilder, your last pic has a double copper elbow, looks like it emerges from a bright orange block. What is this ??

Duncan
Whatever your age you are a wise man. Keep on going strong

Thank you for advice and info supplied by LewZ, hermank and Scratchbuilder. All very useful. Before I decide which way to go, I would still like to hear from anyone who has used the relay shown in my previous post which I found on Ebay. Thank you. 😊

I have several similar "switches" - not identical but the same function. These are not really true switches, but relays.

They function like a switch as follows: You plug the end of the cable into your appropriate channel on your receiver.. You use the contacts on the reliant to control your device, on or off. (It looks like a single pole single throw relay.) You connect your pump to the normally open contact and the common contact on the relay to your power source.

Now you operate that by using an auxiliary switch on the same channel on the transmitter. As long as you keep the transmitter switch on, the pump will run. There is no 30 second burst in these circuits.

Lew
Florida, USA 🇺🇸

https://www.pololu.com/docs/0J60/5.2

Duncan a good day
As promised hereby the pictures of the switch. The switch just cut the battery and canbe used with a normal servo. When you need more info just shout

Duncan.
Although I don’t use it for a Fireboat I have a pump system (see pictures) on a couple of my builds in the form of a bilge pump.
The pump shown is readily available on EBay for £6.00 ish.
The pump is connected to a voltage regulator (next to pump also from EBay)in picture to adjust flow rate and controlled via the throttle ESC using a pressure switch operated by a servo which is hidden in this picture.
My system however will NOT give you burst of flow so may not be of use to you,but may be of interest.
Pictures show two differing pumps in a Corvette and my aircraft carrier.
The nice cheap unit you show looks good and worth a go at that price.May get one myself!
Regards Bill 😉

Duncan the item in the picture is a water pump not a switch. What you need to control the pump is a relay similar to the item you show in your post. This is what I use on my tug.

I will sent you a picture of the switch that’s the easiest

Hi Hermank, Thank you for your reply - what do you mean by an ordinary switch please - I'm new to all these electrics. When looking on some model boat websites they are advertising as well as the water pump a switch to use with them but they are around £21 + postage whereas this one is under £5 including P&P.
The pump is as follows:-

No experience! I used an ordinary switch for the pumps on my Düsseldorf. Are you competing with the local firebrigade?😂😂