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Post by super g on Dec 4, 2013 18:45:14 GMT
On my ds40 I have 2 water tanks. Under the chart table I have an plastic isolation valve on each. To add unnecessary complexity my plan is to replace these with solenoid valves, 6 quid each off eBay.
I will wire them so they take power with the pump running, with a selector switch to chose which valve gets power and opens when the pump runs.
Do you think this will work okay?
It is the first step in a plan to make the chart table lowerable to act as an extra sea birth for starboard tack night sails.
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Post by Don Reaves on Dec 4, 2013 21:00:25 GMT
I would think twice about this modification. Sure, it would be convenient. But as you said, it will add complexity and it will also reduce reliability.
How often do you have to switch tanks? You have to weigh that against the inconvenience of having to raise the chart table. In my last boat, where we had needed to use the bunks in the main cabin, we put the bed away every morning. In your case, this would probably involve raising the chart table, in which case switching tanks would be easy.
Just one person's opinion, of course.
Don
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Post by sailbleu on Dec 6, 2013 5:15:26 GMT
On my ds40 I have 2 water tanks. Under the chart table I have an plastic isolation valve on each. To add unnecessary complexity my plan is to replace these with solenoid valves, 6 quid each off eBay. I will wire them so they take power with the pump running, with a selector switch to chose which valve gets power and opens when the pump runs. Do you think this will work okay? It is the first step in a plan to make the chart table lowerable to act as an extra sea birth for starboard tack night sails. That will surely work fine clouds , and although I'm a high tech guy and gadget lover myself I honestly see no reason to implement that kind of control or setup. Never felt the urge of controling the choise of watertank with solenoids.It's something you do once every .......so many days. Manually close one valve and open the other , nothing to it. But it must be said , it's fancy with solenoids. Mind you though , when being low on energy ( battery voltage) it could very well be that the solenoid refuses to open because the pump draws close to 10 amps and could make the voltage go down too deep , provided you supply the current by means of the same leads as the pump of course. If that would turn into a problem it can be solved with a relay (activated by the pump supply) and seperate supply to the solenoid. Gets kinda complicated no ? Regards |
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Post by electricmonk on Dec 6, 2013 8:18:05 GMT
Before you decide to fit solenoid valves turn both your manual valves off leave it for an hour or so then open only one and start the pump. In other words mimic what your solenoid valves will do. I have just tried this experiment on my 43 and it took many seconds for the water to flow. I think the wait would drive you mad every time you turn a tap on.
Why lower the chart table? I have a piece of ply as a trotter box that allows your feet (trotters) to be supported on a port tack, the nav seat even has the support for this from the factory. Was very easy to make and the chart table is undisturbed.
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Post by super g on Dec 7, 2013 8:45:20 GMT
Before you decide to fit solenoid valves turn both your manual valves off leave it for an hour or so then open only one and start the pump. In other words mimic what your solenoid valves will do. I have just tried this experiment on my 43 and it took many seconds for the water to flow. I think the wait would drive you mad every time you turn a tap on. Why lower the chart table? I have a piece of ply as a trotter box that allows your feet (trotters) to be supported on a port tack, the nav seat even has the support for this from the factory. Was very easy to make and the chart table is undisturbed. Good idea to simulate the solenoids behaviour, I'll try and replicate your symptoms in mine. You're right a delay in water would get tedious, especially topping up my daughters aquarium (in the recent storms I had to do that a lot). Drifting off topic but I'm intrigued by this trotter box, as I cannot see how I would be able to l make any kind of sea berth on the port side without moving chart table. I also thought it would make extra seating when guests are onboard, with suitable re-enforcement. |
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Post by saxofon on Dec 8, 2013 6:21:17 GMT
Hello clouds, I see your point and in my boat (SO37.1) I have three tanks. The tank selectors are unfortunately mounted in the sofa in the saloon so it is very cumbersome to change, as it seems to happen when the saloon is full of people only :-) So I made myself also remotely operated valves. Not solenoid as these require power all the open time, not only when shifting state from/to open/close. You can find it described here: elektronikforumet.com/forum/viewtopic.php?f=3&t=56646Unfortunately in swedish. |
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Post by electricmonk on Dec 8, 2013 6:53:58 GMT
how about leaving both valves open and look at the consumption meter? it works for me.
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Post by sailbleu on Dec 8, 2013 7:19:52 GMT
Hello clouds, I see your point and in my boat (SO37.1) I have three tanks. The tank selectors are unfortunately mounted in the sofa in the saloon so it is very cumbersome to change, as it seems to happen when the saloon is full of people only :-) So I made myself also remotely operated valves. Not solenoid as these require power all the open time, not only when shifting state from/to open/close. You can find it described here: elektronikforumet.com/forum/viewtopic.php?f=3&t=56646Unfortunately in swedish. Only when the pump is running saxafon. Be it directly or indirectly (via relay) Regards |
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Post by sailbleu on Dec 8, 2013 7:25:33 GMT
how about leaving both valves open and look at the consumption meter? it works for me. Mmmmm , not very accurately no , these tank level indicators I mean. But again , depending the number of people on board , switching tanks needs to be done only every so many days. And I think you do have a point there , with regards to the delay of running water due to funny solenoid behavier. About two years ago I have installed a led warning light in one of my panels when the pump is running . Too many times in the past the pump kept running when a tank was empty or nearly , or when there was a small suction leak . When the engine or the radio/television is on you don't hear the waterpump running. On a few occasions my pump had been running for some time , I could feel it on it's body temp. So I connected a very conspicuous red blinking led parall to the pump supply . Guess what ? When my batteries aren't full the led doesn't blink , so I had to put a relay (that activates even on 10 volts) inbetween , this way the led is supplied by separate leads so the voltage is not effected by the voltage drop caused by amps going to the pump. If a led can be effected by such a drop , why shouldn't a solenoid valve that draws much more amps be effected ? PS: I realise that my statement above (first post) , concerning the complexity of running solenoids via relays , stands in contradiction with what I've done with the blinking led. But it's all a matter of priorities . I don't see the necessity of switching tanks electrically , but I do see the necessity of keeping my waterpump alive . I know , closing the main pump switch after use is fullproof , but we tend to forget to do that too many times. So ..... Regards |
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Post by electricmonk on Dec 8, 2013 8:16:33 GMT
OH I see you have a level meter, my SO43 has a consumption meter, it counts how many litres have been used, accurate to within 1 litre on every fill-up - the water "runs out" at 349 litres EVERY TIME. yes its a 400 litre system, the other 51 litres is in the calorifier - specifications don't you just luv em!
The level meter on the fuel tank is a work of total fiction, it shows 3/4 full when there is only about 20 litres left, I keep a log of engine hours and estimate the usage. AND while I am on the subject has anyone else actually timed their engine hour clock? mine does 1 revolution in 50 minutes, so a Yanmar hour is only 50 minutes long - boats . . . . . you would think they could get that bit right in 21st century . . . .
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Post by sailbleu on Dec 8, 2013 8:35:48 GMT
OH I see you have a level meter, my SO43 has a consumption meter, it counts how many litres have been used, accurate to within 1 litre on every fill-up - the water "runs out" at 349 litres EVERY TIME. yes its a 400 litre system, the other 51 litres is in the calorifier - specifications don't you just luv em! The level meter on the fuel tank is a work of total fiction, it shows 3/4 full when there is only about 20 litres left, I keep a log of engine hours and estimate the usage. AND while I am on the subject has anyone else actually timed their engine hour clock? mine does 1 revolution in 50 minutes, so a Yanmar hour is only 50 minutes long - boats . . . . . you would think they could get that bit right in 21st century . . . . Wow , that is what I call very neat stuff , a liter meter (flowmeter) . Jee electricmonk , you really tempt me here you know , never thought about that. But then again , checking the liters passing by when family members taking a shower , is not particular mind easing , ...is it not  I do have a watermaker , about 40 liters an hour , a must considering the time we spend on anchor , but that involves starting the engine or generator for consecutive hours. Although at midday (in the Med , where we'll soon be again) my solarpanels can generate up to 30-35 amps in total. But that's off topic. And about the engine hour meter , well ,....I don't seem to have that problem , mine is a VP engine and their hour meters do not trouble you , they just don't work. Regards |
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Post by super g on Dec 8, 2013 9:48:25 GMT
how about leaving both valves open and look at the consumption meter? it works for me. I've never tried leaving both valves open I'd assumed that as one tank empties the pump would start to draw air in and not empty the second one. Something else to try this afternoon. Consumption metre sounds great. |
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Post by sailbleu on Dec 8, 2013 10:26:28 GMT
how about leaving both valves open and look at the consumption meter? it works for me. I've never tried leaving both valves open I'd assumed that as one tank empties the pump would start to draw air in and not empty the second one. Something else to try this afternoon. Consumption metre sounds great. All will depend on the difference in level of the plumbing. If 1 tank is positioned down and the suction of the second tank goes a bit higher you will for sure draw air. That will result in a pump that keeps running for hours in a row when not noticed. Been there , done that. I have a waterbag as a thirth 150 liter watertank , which is on the lowest point in the boat (next to the bilge) , when nearly empty it always draws air. But this is ofcourse a specific and personal situation , we don't know what yours is. Regards |
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Post by electricmonk on Dec 8, 2013 12:33:47 GMT
Before we fitted our water maker we examined all the various scenarios for tank emptying and filling. I am not a great lover of complexity so I wanted to find out which tank we would need to fill in order to fill both tanks and which tank would empty out first. So in 2008 we ran through all the permutations, aft tank full fill the front tank via the aft tank (after opening both valves) and vis versa. Draining both tanks by leaving both valves open and refilling both but from either the forward or aft tanks - we know how to have fun!
The results of this are that when we leave both valves open both tanks get drained, when the pump runs continuously there is no water left in either tank. I might add this counter to what I was expecting.
We found that we were able to fill the entire system from either the forward or aft tank - if we weren't in a hurry - so a water-maker filling either tank will fill both tanks eventually - water makers don't hurry; we fill our system from the aft tank the plumbing was easier AND when we are on extended passages the forward tank IS isolated in case of contamination and water maker failure, we always have 150 litres reserve. AND, yes there's more we can monitor the aft tank overflow from the helm seat so its easy to find out when the tank is full. easy.
The boat is set-up with a 4 KVa diesel genny (15 hp) and a 220V water maker (echotech no electronics), and 80 watts of solar, the reasons behind this choice of equipment are synergy:
The batteries need recharging around once every two or three days, it takes around 3 hours to recharge batteries with a shore power charger from 30% discharged to around 90% - it would take a week to get them to 95%, and in 3 hours we can make 180 litres of water - around the capacity of the aft tank. SO either the consumption meter reads 180 or the battery voltage is 12.4 ish, either way the genny starts - a manual process I am afraid I press a button. Of course during that 3 hours we have the option to heat water, run any 220v AC equipment hair dryer, vacuum cleaners, washing machine, dive compressor etc. without draining batteries with an inverter. We don't have to run the main engine (56hp) to recharge the batteries or make water.
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Post by saxofon on Dec 8, 2013 12:37:13 GMT
sailblue - sure, only when pump is running which is what i ment. power is needed when the solenoid should be in open state. so when having it on for longer (like a shower) it will consume more. My solution only draws power in the state change, then it doesn't matter for how long it is open or closed. Also after the statechange, power is removed on both + and - so there is no possibility for current leakage. electricmonk - I have tried with all valves open but when the water level is low, the pump is having trouble. I guess depending on seastate there comes in air in the system or so. Having a flowmeter is still on the todo list here. Coupling it with tank level and the yacht server could tell me like "with current water consumption scheme you have enough water for: 11 days"....  |
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Post by super g on Dec 8, 2013 16:46:33 GMT
sailblue - sure, only when pump is running which is what i ment. power is needed when the solenoid should be in open state. so when having it on for longer (like a shower) it will consume more. My solution only draws power in the state change, then it doesn't matter for how long it is open or closed. Also after the statechange, power is removed on both + and - so there is no possibility for current leakage. electricmonk - I have tried with all valves open but when the water level is low, the pump is having trouble. I guess depending on seastate there comes in air in the system or so. Having a flowmeter is still on the todo list here. Coupling it with tank level and the yacht server could tell me like "with current water consumption scheme you have enough water for: 11 days".... Yacht server? I'm imagining you've something with A.I. like HAL off 2001: A Space Odyssey. "Boat why are the tanks empty?" "I emptied the tanks to improve speed sir, for our mission", "What mission? That's it I'm turning you off", "I'm sorry you feel that way but I cannot let you do that......" |
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Post by saxofon on Dec 8, 2013 19:10:39 GMT
 Thanks clouds, now I have some more ideas for enhancement!  It is actually just a cheap beaglebone board, that I for now have hooked up some 1-wire sensors to. Then I get things like temp (the most important beeing the fridge temp so I know the beers are OK), light, humidity, pressure etc.
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Post by super g on Dec 8, 2013 22:28:41 GMT
Hello clouds, I see your point and in my boat (SO37.1) I have three tanks. The tank selectors are unfortunately mounted in the sofa in the saloon so it is very cumbersome to change, as it seems to happen when the saloon is full of people only :-) So I made myself also remotely operated valves. Not solenoid as these require power all the open time, not only when shifting state from/to open/close. You can find it described here: elektronikforumet.com/forum/viewtopic.php?f=3&t=56646Unfortunately in swedish. Impressive set up. I'd looked at motorised valves but thought they always drew current to keep them open. Do you think With two tanks I could just use a single diverter valve like this? www.amazon.co.uk/MISOL-Motorized-Valve-electric-motorized/dp/B00D6FCP36/ref=pd_sim_sbs_lp_13 |
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Post by saxofon on Jul 21, 2014 14:52:48 GMT
Hello clouds, I see your point and in my boat (SO37.1) I have three tanks. The tank selectors are unfortunately mounted in the sofa in the saloon so it is very cumbersome to change, as it seems to happen when the saloon is full of people only :-) So I made myself also remotely operated valves. Not solenoid as these require power all the open time, not only when shifting state from/to open/close. You can find it described here: elektronikforumet.com/forum/viewtopic.php?f=3&t=56646Unfortunately in swedish. Impressive set up. I'd looked at motorised valves but thought they always drew current to keep them open. Do you think With two tanks I could just use a single diverter valve like this? www.amazon.co.uk/MISOL-Motorized-Valve-electric-motorized/dp/B00D6FCP36/ref=pd_sim_sbs_lp_13Very late reply but yes, that valve ought too it. |
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