Northern Lights Genny Oil Pressure and Engine Water Temperature

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JDCAVE

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Apr 3, 2011
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2,994
Location
Canada
Vessel Name
Phoenix Hunter
Vessel Make
Kadey Krogen 42 (1985)
My Northern Lights Genny came with the Series 1-B Control Panel, which is pretty basic. There are no diagnostics coming from the unit. The Series 3 panels has oil pressure, engine water temperature and DC voltage output. This panel is nearly $1,100 USD.

The wiring harness for the control panel is 8 wires if I remember correctly. I had to extend it at the time of installation. Would it be possible to tap into these wires and connect to VDO, Fario or equivalent gauges? Has anyone experience with this and have information on which wire provides what data? Also, would the DC alternator information be useful?

Jim
 
…Another project is to have AC amps into the panel. I should be able to get one of those “donuts” on the “AC in” wiring. I will talk to my electrician about putting in a gauge to monitor that information. Currently I estimate the AC loads on the Genny, with mental calculations on watts from the various appliances. I’m trying to get the Genny loads to at least 75% for the first 100 hours on the Genny. The problem is when the water heater switches off, I need to hear the change in the sound from the Genny. A gauge with real-time information would be ideal.
 
These are the wires for the wiring harness:

IMG_6492.jpg
 
These are the wires for the wiring harness:

View attachment 141107



Jim, I’d start by downloading the owners manual for your generator from the NL web site. They include wiring diagrams with wire colors.

I expect you could piggyback other gauges, but there are subtleties that will come into play. Some devices may be able to piggyback without influencing the existing gauges, but other might interfere. So I would research that carefully with any prospective gauges.

As for current monitoring, I have been pleased with the Blue Sea M2 gauges. They make several models to meter different things, including AC voltage, current, etc. I’d suggest trying to locate the sense points for the gauge such that it’s metering generator or shore power, whichever is selected. Then you can use it equally to monitor either one, which would seem useful.
 
Thanks TT. Of course I will check things out carefully before proceeding. It seems the “sending units” for both the oil pressure and water temperature come in 1 and 2 station versions. I suspect that what is on the Genny is a 1 station version. I’m guessing gauges may require different “impedances” or whatever so would be specific to sender type.

I’m just thinking, damn but those panels are expensive when I only need 2 or 3 gauges, which I could probably buy for $50-60 each. Perhaps less. That and a terminal strip and some rain terminals and I’m away to the races.

Yes, I will source the blue seas version. But I won’t touch the AC panel. I’ll bring in an electrician for that.

Jim
 
I did the same thing. I have a small NL panel in my 120 panel board, and the NL panel with gauges was in the engine room near the genset, worthless.

I extended the harness and spliced them together at the helm. Now I have NL panel with gauges above the helm. Note, pull an extra pair when you extend it, just in case.

I do not have a frequency meter on boat, but have the GB and and volt meter. After changing refrigeration to 12 vdc, my genset load is much less, almost half at Max 5.5 kw.

If you add volt, amp, and frequency meter place it downstream of power source selector switch then you can see everything.
 
This might be in my blog, grandbankschoices. Not sure, one of first mods I did.
 
Choices: did you use the NL gauges, or did you use some other make? I have already spliced the wiring harness to extend it, but I do not have the gauges.

Jim
 
I used the original NL gauge panel. Someone had a set for sale on here, I think he had the Willard being refitted in Mexico, name escapes me but he is a frequent poster. Weebles? Those panels show up for sale often.

It took a day to sort out the wiring and route it clean. Check the back lighting, mine is really dim, I need to pull it and check bulbs.
 
I just remembered I ordered a new plastic face when I moved it so now it's like new.

Check with Weebles and see if he sold his.
 
My Northern Lights Genny came with the Series 1-B Control Panel, which is pretty basic. There are no diagnostics coming from the unit. The Series 3 panels has oil pressure, engine water temperature and DC voltage output. This panel is nearly $1,100 USD.

The wiring harness for the control panel is 8 wires if I remember correctly. I had to extend it at the time of installation. Would it be possible to tap into these wires and connect to VDO, Fario or equivalent gauges? Has anyone experience with this and have information on which wire provides what data? Also, would the DC alternator information be useful?

Jim

You can do this easily. But are you saying you want to add another set of gauges to install in another place so that you have 2 gauge panels? O just change out existing panels on the NL panel.

If you just want to put in your choice of gauge then you just need to purchase the correct gauge with the correct Ohm range for the oil pressure and engine temp. It should be listed on the wire diagram or the guage. For DC voltage I would just wire in a digital DC volt gauge to check for voltage rise after start. That is unless you are using the gen alternator for something fancy.

If you want to add an additional set of gauges you will have to change the sender on the oil pressure and temp sender to a dual helm set up since the ohm ranges will be different. First you will need to figure out the ohm range of the existing oil pressure and water temp gauges/ senders and then find the corresponding sender for dual station.

 
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Thanks all. Barking Sands: that is what I was looking for. To be clear, I don’t have any existing gauges. And I don’t need sender for two stations. This is the panel I have:
IMG_6493.jpg
I would like to add the oil pressure, water temperature and DC volts. The above panel has 6 wires, but it connects to an 8 wire harness. So I figure, it I find the gauges with the correct impedance, I should be on the right track.

Jim
 
As per TT’s suggestion, this is the wiring schematic, DC engine, 12 VDC:

IMG_6498.jpg

This is the wiring schematic for the gauges with a terminal strip as shown:

IMG_6499.jpg

So I plan to split the wiring harness to a terminal strip, reconnect the existing panel harness to the terminal strip, then split off the connections to the new gauges: DC voltage, Water Temperature and Oil pressure, after first determining the correct gauges based on the sending units.

Jim
 
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Got it. Sorry for the late reply. So my next question is: do you know if the genny has the sensors installed into the engine? An oil pressure sender and water temp sender? You will have to physically see if they are installed.

There may be no sensors installed and only switches to activate shut down. Meaning there are no senders installed. In that case you would have the other end of that harness wires also bagged or zip tied off to the side.

You also could have the senders installed and have wires hooked up to the senders. In that case you just need to identify the senders as Oil Pressure and Water Temp and look at the color wires coming off and write them down. It is likely there will only be one colored wire coming off each. The other side of the circuit (both) is grounded at the sensor casing to the engine and back to the panel gauge when installed and wired.

If you have no senders installed that kind of makes it easy since you can buy matching gauges with senders. If they are installed an email to Northern lights should tell you the ohm range type. Or we could guess with about 75% accuracy. Or if you have an ohm meter we can put the meter to ohms and put the red on the center output wire and the black to case ground and read the ohms not running and then running and that would fill us in too.

Here is another small video I made talking about senders vs switches. In the video the two newer gold ones are both senders. The big one being oil pressure and the small being temp. You might be able to find them on your engine after looking at these. Temp is usually up front somewhere near the fresh water pump and thermostat. Oil pressure sometimes along the left side not to far from oil filter.

 
Been awhile, but I just tied to the NL basic panel in my 120 panel.

I recall all the sensors and wiring was there already. The extra wires were folded back in the harness. It did have a split NL harness with a multipin plug. I cut it off and spliced there with a 12 pair wiring bundle. The NL bundle was 5' short. Extras for just in case I want to add something else.

Both my panels are fully functional.

I am blown away GB did not do this at the factory.

I did not want to have it go through the CAN bus system. When we anchor everything Garmin is usually off. The second panel is overhead above steps to below, and easy for us to glance at, with the GB amp and voltage meters close. Simple monitoring.
 
Got it. Sorry for the late reply. So my next question is: do you know if the genny has the sensors installed into the engine? An oil pressure sender and water temp sender? You will have to physically see if they are installed.

Oh yes. The senders are in place and the wires for each of these are in the wiring harness and identified. Water temperature is “Tan”, oil pressure is blue. I presume each gauge requires 2 wires, hot (respective colour) and ground. As mentioned in the OP, NL has a 4-gauge panel, but it is expensive.

The main question I have is: how do I know if any particular non-OEM gauge is compatible with the sending unit?

Jim
 
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…if you have an ohm meter we can put the meter to ohms and put the red on the center output wire and the black to case ground and read the ohms not running and then running and that would fill us in too…

Ok. Got it. I’ll have to splice the bundle off onto a terminal strip in order to do this. Alternatively, I could take the impedance right at the sender.

Another option is to phone northern lights technical team and see if they know the impedance of the senders.

Jim
 
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Been awhile, but I just tied to the NL basic panel in my 120 panel.

I recall all the sensors and wiring was there already. The extra wires were folded back in the harness. It did have a split NL harness with a multipin plug. I cut it off and spliced there with a 12 pair wiring bundle. The NL bundle was 5' short. Extras for just in case I want to add something else.

Both my panels are fully functional.

I am blown away GB did not do this at the factory.

I did not want to have it go through the CAN bus system. When we anchor everything Garmin is usually off. The second panel is overhead above steps to below, and easy for us to glance at, with the GB amp and voltage meters close. Simple monitoring.


Thanks for that. Perhaps the reason GB didn’t do this was because it was an option in the build (or post build) and the original owner was unaware of the benefits of what you have done. As you already had the correct NL gauges, you didn’t have compatibility concerns with the senders.

Jim
 
Ok. Got it. I’ll have to splice the bundle off onto a terminal strip in order to do this. Alternatively, I could take the impedance right at the sender.

Another option is to phone northern lights technical team and see if they know the impedance of the senders.

Jim

Its almost certainly going to be this range for oil PSI gauges
US ohm range (240 - 33 Ohm), 1/8" NPTF
And from your wire diagram you posted oil pressure will be the blue wire you showed earlier. And as per your diagram it is a single wire gauge that is grounded through the block.
Your oil PSI wire is Blue. Take your meter and set to Ohms. Red lead shoved in the end of the blue wire. Black lead put on some good ground. At 0 psi it should read 240 ohms. Start the genny and around 40 psi it should be half way between 240 and 33 ohms (interpolate in regards to your running pressure as to corresponding ohms since the scale of the 240-33 ohms equals 0-80 psi)


Temp Temp is Tan wire. Do that same procedure for temp. But you dont have a zero value since temp senders read some variable temp always. But it should be like this:
Temperature range: 100° F to 220° F
Resistance:
100° F = 450 Ohms
175° F = 99 Ohms
250° F = 29.6 Ohms
 
Thanks BS. I understand. I should also be able to take these measurements at the actual senders, prior to splitting the bundles. That might be the best initial approach.

I had to butt-connect the wiring harness in the first place, as it wasn’t long enough, so I’m not shy on doing this.

Jim
 
Thanks BS. I understand. I should also be able to take these measurements at the actual senders, prior to splitting the bundles. That might be the best initial approach.

I had to butt-connect the wiring harness in the first place, as it wasn’t long enough, so I’m not shy on doing this.

Jim

Yep...you got this brother:thumb:

Show us your end results when done!
 
Here’s a bit of an update:

I purchased and installed Faria oil and water temperature gauges in the range specified in the NL manual. The water Temperature looks about right, however, the oil pressure gauge reads about 1/2. The current oil pressure sender is VDO. The Faria sender has a different thread fitting, complicating things so will stick with VDO.

I have determined from the impedance measured from the wire from the sender that the oil pressure is about 60 psi. I checked the NL manual and couldn’t find the info I was looking for.

I could take off the sender and put on a temporary mechanical gauge as a check, but I don’t like mucking around with senders. They are quite fragile and easily damaged. Ask me how I know!

I have determined the VDO gauges in the specified range from the NL wiring diagram should do the trick.

IMG_6549.jpgIMG_6551.jpg
 
After a hiatus on this project, I have finally figured out the gauge sender issue. Part of the delay was due to considering the difference between NPT and NPTF fittings and whether the two were compatible. After considerable, to and frowing, I pushed ahead, and replaced the NPT sender that was installed by Northern Lights, with a Faria NPTF sender, using a small amount of pipe dope on the threads. This seems to work without leaks. The gauges now show readings that are reasonable after several minutes with the generator running.

My next step is to get an ammeter installed on the on the wire coming out of the “Ship-Off-Shore” selector switch. This will allow me to determine the AC loads on the panel, regardless of whether it shore, power or generator power. I have determined where those wires go, and they are common to both power from the generator and power from Shore. I have attached a photograph showing where those wires come out. There are two of them coming out and they go to separate sides of the circuit panel. I suspect, but I am uncertain, but one side goes to the inverter side of the panel and the other one goes to the non-inverter side of the panel. Should the donut for the ammeter go on both of these wires? Or only one?
 

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I am in the process of this same thing on NL mk series but took a different approach. I cannot see any information on the gensets other than in the bilge

. I have a large nema 2000 network and I use the maretron system. I installed a clm100 (current loop monitor) This allows me to install any standard 4-20 ma sender. I ran a new sender cable to the genset and to the loop monitor. I have installed a temp sender and a second oil pressure sender. I now have my gen set oil and temp on the nema 2000 network and can read it from any screen on the boat.

I have also added temp to my transmissions, pressure for the transmissions, Hydrolic system pressure and transmission. Also working on water pressure, and heater temp. Pretty cool stuff. I can also alarm everything to ring a whatever value i pick. I can make the temps ring if they only go up 5 deg over normal. I also have end switches to monitor the water flow for the gensets, engines, and hydraulics through the same maretron system SIM 100 module. I will also install heat sensors on the exhaust elbows that trip at a certain temp. through the sim100.

One thing I realy like about it is when you are operating the boat, you do not need to be looking at the gauge screen. If there is a problem a fairly large bar will pop up on every Garmin screen on the boat. List the alarm or warning and options to clear or silence.
 
Very good Greg. I have seen the Maretron option and had considered it as I already have a limited Maratron N2K system, but it would have been a bigger investment than I was prepared to make right now. I got a simple analogue Blue Sea ammeter and that will suffice for my purposes.

Jim
 
I can read incoming voltage and current on each leg shore power or gendet at the helm. I assume you don't have this?
 
I can read incoming voltage and current on each leg shore power or gendet at the helm. I assume you don't have this?

No. There is no AC Ammeter currently installed, and it’s a shortcoming, IMO. You can do the rough calculations in your head from equipment specifications, but draws such as water heaters are difficult to take into account as they switch on and off silently. I would like to have the measurement of current take place on the wires exiting the switch so the draws on both shore and generator sources are monitored.

Jim
 
Very good Greg. I have seen the Maretron option and had considered it as I already have a limited Maratron N2K system, but it would have been a bigger investment than I was prepared to make right now. I got a simple analogue Blue Sea ammeter and that will suffice for my purposes.

Jim

Jim
The primary expense of your system is done. Building out the system is not that costly. You do need the marathon monitor boxes. You get up to 6 channels each. You do not need to use the maretron sensors witch saves a lot.
 
I finally finished this up a couple of weeks ago. Note that I put additional overcurrent protection on the panel as the panel lighting uses 22 gauge. Here are the results.

IMG_7138.jpg

Hmmm! Not sure why the second photo is on its side!

Jim
 

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