Help with wiring my new eye candy

Well I got a new Raymarine E90W chart plotter and Ray 18" HD radar to replace my Raytheon RL 80 CRC legacy plotter and radar. I will wire it myself and the current wiring at the helm behind the wheel looks like a bowl of spaghetti.

I'm not going to rewire everything but I do want to do a proper wiring job on the new stuff. I think all the new connections should be in boxes with separate boxes for nav comm and power. However I'm open to suggestion. Where best to buy boxes and how the heck does one deal with these tiny 24 or higher gauge wires coming out of the plotter?

My old radar was powered by the chart plotter. The new unit has a separate power cord for the radar separate from the plotter. I am assuming the plotter powers the radar on and off even though the power for the radar comes from a different circuit breaker. What I don't want is for the radar to be powered on any time there is DC power at the breaker. Is this generally correct, plotter acts as a on/off switch for the radar.
The instructions say a 10 amp thermal breaker or a 15 amp fuse is required for the radar.
I have the 10 amp breaker available for the radar, but I’m unclear if it’s a thermal breaker, how do I tell.
The radar has 3 wires in addition to the data connection to the plotter. One wire is power, one is battery negative and one is drain (screen). Is it required that the drain (screen) wire be connected to the bonding system on the boat?

My plan is to power the plotter, heading sensor, depth gauge, GPS sensor and autopilot from one circuit breaker then to an existing switch on the helm labeled "autopilot". The radar will have it's own CB but not switched. This way when I'm on the hook, I can turn the autopilot switch off and all the nav stuff will be un-powered and not running the batteries down.

Suggestions please.

The installation manuals will answer a lot of your questions like what to do with the drain connection for the radar. It will also spell out fuse/breaker requirements.

Boxes are a nice touch and become increasingly important where connections are otherwise exposed to getting banged and bumped. But if it's all inside a protected console of some sort, a terminal strip would be fine too. Many people just splice wires together, and if done properly it's OK for one-to-one wire connections. I like the heat shrink butt splices. But for more than 1-to-1, a terminal strip is the way to go. Terminal strips are also good where you might want to add things in the future, so I would definitely use them for 0183 connection points.

Are your breakers push-button breakers that can be reset, but can't act as an off switch? Or are the the style that also act as an on-off switch?

Keep in mind that the breaker is there to protect the wires, and that all the wires connected to the breaker need to be able to handle the full current of the breaker. If you drop to a smaller wire, there should be an in-line fuse to subsequently protect to smaller wire. Unfortunately, this is often not done. Powering everything off one breaker means a pretty big breaker; the AP alone probably draws a bunch of current.

Here's what would be my preferred setup for what you describe, but I understand you have to work within the constraints of your boat and budget. I think I'd go for a separate switch/breaker for 1) Radar, 2) Autopilot, 3) Chart plotter, 4) GPS, radio, and other misc stuff. This way you can separately power things, isolate one if there is a problem, and simplify your wiring. I also like being able to keep the VHF and GPS powered on with everything else off. That ensures you always have communications, and with the GPS on your DSC function will work.

If you are forced to use a single push-button breaker and on/off switch, which I think is what you have now, then I'd consider putting a Blue Seas fuse box just down stream of the on/off switch. From there you can break out each device, fuse it with the proper size fuse, and gain some isolation of components for a more resilient setup.

The easiest way I wire electronics is to use a Blue Seas fuse panel that is fed from the CB panel. I have seen so many hot wires from breakers that don't trip...I'm going back to fuse panels fed by breakers to minimize the number of breakers (but they are convenientas switches). Each piece can be turned off and on from the machine itself and keeps the wiring runs short.

For instruments that don't have an on/off switch such as the Raymarine autopilots for years...when you turn off the CB to the fuse block it will be off or you can just add a small switch right next to the pilot where it is mounted.

In line fuses for many electronics are for the wiring to the unit...these can be cut out then and just use the appropriate size in the new fuse block. But be careful, in the manual it usually says if the external fuse is for the wiring or interior components and may only be an amp fuse or less...those have to stay nd make a note someplace in case that machine craps out and the fuse in the fus eblock doesn't restore it.

The breaker you have for the radar is a tough call..many newer breakers I am pretty sure are magnetic.

I would suggest running the autopilot on its' own breaker. It draws quite a bit when the pump is running. The data wires can connect through a newmar type or eurostrip connector.. PVC boxes and glands are available from McMaster Carr or Imtra. Imtra is labeled marine and cost 4 times as much. If you are wiring in a protected space the boxes are not really necessary but make the job very sanitary. I would cover the ends of the stripped wire with dielectric grease.

Thanks guys.
I have the switch type breakers which means I can switch the circuit off and on as desired. Currently the Radar is on one C/B, the VHF radio is on one C/B and all the rest of the nav equip on a C/B consisting of the autopilot and related equipment, 2 GPS's and related sensors. As you suggested, I'll split off the autopilot and related equipment to it's own C/B. For safety, I like the idea of the VHF radio on it's own C/B and may hot wire with a fuse my second GPS (Garmin 740) to the house bank. Any thoughts on this?

I need some help understand NMEA 0183 ground or shield. Currently my GPS sensor and heading sensor are connected to my plotter via it's NMEA 0183 connections with the shield wire of each component and the plotter connected to battery ground. Reading the instructions on my new plotter, it seems to indicated that each component like my heading sensor should be connected to the plotter with the data wire which is indicated by +VE connected to the in-port connection of the plotter and the shield wire connected to the -VE in-port connection of the plotter. It makes no mention of connecting this to battery ground like my current setup. I understand the power connection to the plotter is connected to battery ground, I'm just unclear about NMEA 0183 ground or shield.

You can leave the existing drains attached to the ships ground as the are. The new Raymarines do not use a drain. Just use the ve+ and ve- to connect your peripherals.

Well now that I look at it more closely, the shield wire from my heading sensor must go to battery ground or else it would not have a ground connection. The heading sensor is not powered by the plotter but has a separate power source. So the shield wire must act as a power ground AND a communication ground. Correct?

What are you guys thoughts on using the automotive spade fuses instead of the glass wire fuses?

I like blades...less prone to breaking and they are self cleaning to a degree if you pull them and spray them once a year.

I like blades because the are less prone to breaking and if pulled and sprayed once a year never seem to have issues.

Plus I like that I can read the amperage easier!!!