dhays
Guru
- Joined
- May 26, 2015
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- 9,045
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- United States
- Vessel Name
- Kinship
- Vessel Make
- North Pacific 43
Those of you who were entertained by my oil pan heater will love this.
I installed something over the weekend to solve a problem where none really existed.
So, I have two 200 gal fuel tanks and a single engine. I normally draw from one tank and return to the same tank. I have to change tanks to keep the boat trimmed. My boat also came with a crossover line with a Reverso transfer pump controlled by a switch at the helm.
So I have three ways to equalize fuel level. 1) Burn from the more full tank. Very effective but takes some time. 2) Return fuel to the opposite tank that it is being drawn from. Extremely fast and easy, however there is the risk that I might forget and over fill a tank. There is also the possibility of making an error when changing the fuel manifold, cutting off a return line which would be very bad. 3) Use the nice fuel transfer pump.
I never do #3 because the toggle on the dash at the Helm is a momentary toggle. I can send fuel either direction but I have to hold the dang toggle over. At 3 gpm you have to standing there holding that stupid toggle for a long time to get much fuel transferred. So I decided to do something about it.
First step was to order an On-Off-On DPDT latching switch to replace the DPDT momentary toggle. The only problem with this is that it is possible (probable?) for me to forget about it, again causing an over full tank and resulting spill.
Then one of the many folks on TF who is smarter than I mentioned a timing relay in the thread about intermittent wipers. It got me thinking.
I decided I wanted a way to have a timed transfer of fuel (without using a mechanical dial timer which would not be attractive in the PH) that would also give me an visual indicator that it was active.
I found this timer relay on Amazon. It is made by 3rdbrakeflasher and seemed to be able to do what I wanted, as long as I could figure it out. They make two version, a 5 amp and 10 amp. I ordered the 10 amp since my pump uses 10 amps.
I then ordered this 16mm LED button switch in red. My thought was to use this to trigger the timer. When triggered the relay would send power to the DPDT toggle which would control which way the pump would run. The LED would be lit while the timer was active and then go out. The pins on the switch are really small so I also picked up a pigtail for the switch (actually two as they are sold in pairs).
I then got a little worried. The timer relay is rated for 10 amps at 12v. My pump says it runs at 10amps, but often we have more than 12v when the batteries are being charged while at the dock or under way. Not knowing anything about electricity, I decided that it may be too close to the timer relay's rating to be comfortable. So I decided to add a 30amp relay. So the timer relay would send current to the 30 amp relay which would in turn power the DPDT switch which would direct which way the pump ran. Simple right? I found a 30 amp relay with pigtail connector at an autoparts store, then found that Radio Shack had them for 50% off. You can get them from Amazon even cheaper.
The timer relay can be programed to do most anything you could want, but to program it there are two leads which need to be grounded in certain sequences to set the behavior of the timer as well as the length of time. You can do this by simply shorting those wires to a ground, but given that the whole thing would be buried underneath the helm station, it would be a real pain to get at to change the programing. So I bought some push button micro-switches from Radio Shack and some small project boxes from Amazon.
So I had the stuff, I just didn't know how to put it together. The 3rdbrakeflasher.com website has an instruction manual that is pretty good. It gave me some basic ideas and I came up with this schematic.
It had been a long time since I have done any soldering but I soldered up a harness for the ground connections, installed the micro-buttons in the project box and ran it to just inside the DC electrical cabinet in the PH. I installed the LED push button switch right above the toggle switch at the helm between the fuel tank indicators and crammed all the wiring, relays and connections into a larger project box I picked up at Radio Shack and mounted that under the helm console where all the other wiring is.
Usually, when I design and build something, it doesn't work at first. I usually have to trace down either design errors or problems created from my complete incompetence at anything electrical or mechanical. In this case at 5:00am this morning (I had a lot of projects I was working on Friday and Saturday) it worked from the beginning as soon as I turned on the breaker at the DC panel for the fuel transfer pump. (It has always had its own circuit).
So the procedure is this.
1. Turn on the power for the pump at the panel (I normally keep unneeded items powered off at the panel).
2. flip the toggle in the direction that I want the fuel to flow.
3. Push the red button.
As soon as it is pushed (it is momentary), the LED lights up and the pump starts to go. I set it for 10 minutes which will transfer 30 gallons of fuel. After 10 minutes the LED goes out and the pump shuts off. I can interrupt the pump cycle by simply pushing the button again to cancel the timer interval. I can also flip the toggle to the center off position. In this case the timer will still run and the switch will be powered, but the pump will be off. If I want another 30 gallons of fuel transferred after the cycle has completed I can just push the button again and get another 30 gallons transferred.
Here is what it looks like with the timer on and off.
I installed something over the weekend to solve a problem where none really existed.
So, I have two 200 gal fuel tanks and a single engine. I normally draw from one tank and return to the same tank. I have to change tanks to keep the boat trimmed. My boat also came with a crossover line with a Reverso transfer pump controlled by a switch at the helm.
So I have three ways to equalize fuel level. 1) Burn from the more full tank. Very effective but takes some time. 2) Return fuel to the opposite tank that it is being drawn from. Extremely fast and easy, however there is the risk that I might forget and over fill a tank. There is also the possibility of making an error when changing the fuel manifold, cutting off a return line which would be very bad. 3) Use the nice fuel transfer pump.
I never do #3 because the toggle on the dash at the Helm is a momentary toggle. I can send fuel either direction but I have to hold the dang toggle over. At 3 gpm you have to standing there holding that stupid toggle for a long time to get much fuel transferred. So I decided to do something about it.
First step was to order an On-Off-On DPDT latching switch to replace the DPDT momentary toggle. The only problem with this is that it is possible (probable?) for me to forget about it, again causing an over full tank and resulting spill.
Then one of the many folks on TF who is smarter than I mentioned a timing relay in the thread about intermittent wipers. It got me thinking.
I decided I wanted a way to have a timed transfer of fuel (without using a mechanical dial timer which would not be attractive in the PH) that would also give me an visual indicator that it was active.
I found this timer relay on Amazon. It is made by 3rdbrakeflasher and seemed to be able to do what I wanted, as long as I could figure it out. They make two version, a 5 amp and 10 amp. I ordered the 10 amp since my pump uses 10 amps.
I then ordered this 16mm LED button switch in red. My thought was to use this to trigger the timer. When triggered the relay would send power to the DPDT toggle which would control which way the pump would run. The LED would be lit while the timer was active and then go out. The pins on the switch are really small so I also picked up a pigtail for the switch (actually two as they are sold in pairs).
I then got a little worried. The timer relay is rated for 10 amps at 12v. My pump says it runs at 10amps, but often we have more than 12v when the batteries are being charged while at the dock or under way. Not knowing anything about electricity, I decided that it may be too close to the timer relay's rating to be comfortable. So I decided to add a 30amp relay. So the timer relay would send current to the 30 amp relay which would in turn power the DPDT switch which would direct which way the pump ran. Simple right? I found a 30 amp relay with pigtail connector at an autoparts store, then found that Radio Shack had them for 50% off. You can get them from Amazon even cheaper.
The timer relay can be programed to do most anything you could want, but to program it there are two leads which need to be grounded in certain sequences to set the behavior of the timer as well as the length of time. You can do this by simply shorting those wires to a ground, but given that the whole thing would be buried underneath the helm station, it would be a real pain to get at to change the programing. So I bought some push button micro-switches from Radio Shack and some small project boxes from Amazon.
So I had the stuff, I just didn't know how to put it together. The 3rdbrakeflasher.com website has an instruction manual that is pretty good. It gave me some basic ideas and I came up with this schematic.
It had been a long time since I have done any soldering but I soldered up a harness for the ground connections, installed the micro-buttons in the project box and ran it to just inside the DC electrical cabinet in the PH. I installed the LED push button switch right above the toggle switch at the helm between the fuel tank indicators and crammed all the wiring, relays and connections into a larger project box I picked up at Radio Shack and mounted that under the helm console where all the other wiring is.
Usually, when I design and build something, it doesn't work at first. I usually have to trace down either design errors or problems created from my complete incompetence at anything electrical or mechanical. In this case at 5:00am this morning (I had a lot of projects I was working on Friday and Saturday) it worked from the beginning as soon as I turned on the breaker at the DC panel for the fuel transfer pump. (It has always had its own circuit).
So the procedure is this.
1. Turn on the power for the pump at the panel (I normally keep unneeded items powered off at the panel).
2. flip the toggle in the direction that I want the fuel to flow.
3. Push the red button.
As soon as it is pushed (it is momentary), the LED lights up and the pump starts to go. I set it for 10 minutes which will transfer 30 gallons of fuel. After 10 minutes the LED goes out and the pump shuts off. I can interrupt the pump cycle by simply pushing the button again to cancel the timer interval. I can also flip the toggle to the center off position. In this case the timer will still run and the switch will be powered, but the pump will be off. If I want another 30 gallons of fuel transferred after the cycle has completed I can just push the button again and get another 30 gallons transferred.
Here is what it looks like with the timer on and off.
