Installing my new vhf

[maury]

I bought a Uniden 725 gps and instructions recommend connecting direct to power source if possible. Main Contemplating electric panel or unused load connector on Rover solar connector which is next to it or do a 9’ line to house lithopo battery. Thoughts?

[rslifkin]

A breaker on the main DC panel should be a perfectly fine source as long as the wiring is all sized appropriately to avoid excess voltage drop.

[Shrew]

I'd put it on a fused switch at the helm or a breaker on the DC panel. Wiring everything directly to the batter is not scalable. Image if every device had to be brought all the way back to the battery.

If voltage drop is an issue, then I'd look at making sure the line an ground to the panel was sized properly and had no corrosion.

Ridiculous!!

[wyb2]

Originally Posted by maury

I bought a Uniden 725 gps and instructions recommend connecting direct to power source if possible. Main Contemplating electric panel or unused load connector on Rover solar connector which is next to it or do a 9’ line to house lithopo battery. Thoughts?

I think you meant ‘contemplating main electric panel’. Presumably you have a DC distribution panel with either breakers or switches and fuses. 100% connect it to that. Preferably it’s own switch, but could be common with something that it makes sense to be turned on and off with the VHF.

I think they are trying to tell the guy with the 19’ runabout not to T off his nav light wires. I pulled up the manual real quick, it doesn’t even mention installing a fuse… not very well written in my opinion.

[Be Free]

Originally Posted by wyb2

I think you meant ‘contemplating main electric panel’. Presumably you have a DC distribution panel with either breakers or switches and fuses. 100% connect it to that. Preferably it’s own switch, but could be common with something that it makes sense to be turned on and off with the VHF.

I think they are trying to tell the guy with the 19’ runabout not to T off his nav light wires. I pulled up the manual real quick, it doesn’t even mention installing a fuse… not very well written in my opinion.

I've installed less than a dozen VHF radios on my various boats but all of them came with an inline holder wired into the positive cable near the radio.

[Cwens]

Originally Posted by Be Free

I've installed less than a dozen VHF radios on my various boats but all of them came with an inline holder wired into the positive cable near the radio.

With boat wiring, people mistakenly think "It's only 12 volts; what's the big deal?". The hazard isn't shock, it's fire. A typical lead-acid battery (and modern lithium batteries even more so) will source mind-bending amounts of current if asked to do so; a short circuit will heat wires to white hot in seconds and will start a fire.



Any wiring run needs to be fused close to the source (i.e., close to the battery.) If the fuse in the wire is near the radio, and if the other end is connected "directly to a power source," then the entire run of wire from the battery up to the fuse is unprotected. A fault in an unprotected wire (for example, a poorly supported wire rubbing against a metal component of the boat, and eventually wearing through the insulation) will heat the wire hot enough to start a fire.

[Shrew]

Originally Posted by Be Free

I've installed less than a dozen VHF radios on my various boats but all of them came with an inline holder wired into the positive cable near the radio.

I have a huge breaker protecting the entire circuit from the battery to the DC panel. The helm circuit is on a breaker on the DC pane that protects the circuit from the DC panel to the Helm. (This helm circuit is way oversized for future upgrades and to attempt to prevent voltage drop). Devices are then placed on fused switches or inline fuses from the positive bus to the device to protect the circuit from the helm to the device.

This way all legs are fused based on the size of the downstream circuit. There is no need to run each device back to the battery with a rats nest of inline fuses.

I agree the inline fuse shouldn't be on the radio side. It should be where the radio lead is connected to the positive bus.

[team karst]

Actually, the radio fuse is meant to protect the radio from reverse polarity events.

[Wotname]

Originally Posted by team karst

Actually, the radio fuse is meant to protect the radio from reverse polarity events.

Err...

[Wotname]

Originally Posted by maury

I bought a Uniden 725 gps and instructions recommend connecting direct to power source if possible. Main Contemplating electric panel or unused load connector on Rover solar connector which is next to it or do a 9’ line to house lithopo battery. Thoughts?

The owners manual contains most of the necessary data required to wire the radio.

Page E-5 tells you to connect to the vessel's power supply (not the power source). The vessel's power supply is dependant on the design of the vessel's electrical system. In your case, that is most likely to be the main DC distribution panel or perhaps a 12V 'hot' bus if fitted (i.e. an 'always ON' bus).

Page E-5 also tells you what wire gauge to use (dependant of cable length). Good electrical practice is always to fuse circuit wiring and Uniden expects you to do that - note page E-44.

The radio won’t turn on.
If you turn the radio on immediately after turning it off, the power may not turn on due to data saving. Wait for few seconds and turn it on again.
Check the fuse.
Check polarity.
Check the line voltage (10.5V to 16V).

Fuse size is dependant on wire size selected (page E-5)