

🔴 Switch smart, power strong — never miss a beat on the water or road!
The Blue Sea Systems 9003E e-Series Single Circuit Battery Switch is a compact, ignition-protected rotary switch rated for 32V DC and 325A continuous current. Designed for marine and RV applications, it offers versatile mounting options, tactile controls for low-light operation, and robust copper studs that accept multiple cables for secure, low-resistance connections. Ideal for isolating or combining battery banks, it ensures reliable power management in tight spaces and harsh environments.


| ASIN | B000MMC914 |
| Actuator Type | Rotary |
| Best Sellers Rank | #7,123 in Sports & Outdoors ( See Top 100 in Sports & Outdoors ) #2 in Boat Battery Switches |
| Brand | Blue Sea Systems |
| Circuit Type | 1-way |
| Color | Red |
| Compatible Devices | Boat lights, Boat horns, Other marine electrical devices |
| Connectivity Protocol | X-10 |
| Connector Type | Idc |
| Contact Material | Stainless Steel |
| Contact Type | Normally Open |
| Control Method | Touch |
| Control Type | On/Off |
| Controller Type | Ring |
| Current Rating | 1 Microamps |
| Date First Available | October 1, 2001 |
| Department | 0.00 |
| Global Trade Identification Number | 00632085900359 |
| International Protection Rating | IP66 |
| Is Discontinued By Manufacturer | No |
| Item Weight | 1.3 pounds |
| Item dimensions L x W x H | 2.9 x 6.38 x 8.63 inches |
| Item model number | 9003e |
| Lower Temperature Rating | 1 Degrees Celsius |
| Manufacturer | Blue Sea Systems - Sports |
| Mounting Type | Panel Mount |
| National Stock Number | 5930-01-543-3693 |
| Number of Items | 1 |
| Number of Positions | 1 |
| Operating Voltage | 48 Volts |
| Operation Mode | ON-OFF-ON |
| Product Dimensions | 2.9 x 6.38 x 8.63 inches |
| Terminal | Spdt |
| UPC | 632085900359 |
| Unit Count | 1.0 Count |
| Upper Temperature Rating | 1 Degrees Fahrenheit |
| Vehicle Service Type | Marine Boat |
| Wattage | 16800 watts |
T**N
Quality product
Used these on the solar system in my travel trailer. Works great to isolate and test / charge batteries individually.
D**G
Great fit and easy confident switching.
This is the perfect switch I need to add the second battery to my pontoon boat. Strong lugs and easy to mount securely. Slots make it easy to route the cables cleanly, too.
K**A
Accessable From Any Side, Easy to Turn
Excellent product. After having long thought that Perko was the gold standard in marine accessories, I took a chance and changed brands when the sea air had finally given my battery switch all it could take. I am very happy with my choice. Functionally, they are all pretty much the same. The difference for me was, since the unit is open on all 4 sides and not just the bottom, routing your wires is very easy. The switch is also physically easier to turn than the one I took out ( which is good on those bad arthritis pain days).
D**.
Highly Recommended!
Solidly built, easy to install/use, and should last a long time. The switch functionality is very good and handles a lot of current. My only complaint is the lack of a back which leaves the connections exposed. I used a piece of rubber to put on the back so the connections weren't exposed to the metal boat frame I mounted it to. I highly recommend this brand-name unit over other cheaper products. This is a clear scenario where you don't want to get bit by the "you get what you pay for" truth.
G**G
Quality
Appears to be well made but too large for the location I wanted to install it.
N**Y
Solved battery trickle problem, strong with nice flush mount
The switch was a breeze to install, feels very solid, and I expect it to last a long time. I'm sure this is a little over-kill for my single marine battery, but I'm willing to pay an extra twenty bucks for peace of mind. This switch has a very high threshold for the load of amps that occur upon starting the engine, and it's size and weight imply that I won't be replacing it any time soon. The ability to flush-mount it worked great and keeps it looking professional. Regarding my specific setup: I have a standard marine battery running to a 120hp Yamaha outboard. For the last couple seasons I have had an issue with the battery dying if I didn't use the boat for several weeks. Physically disconnecting the battery terminals after using the boat solved the problem, but it wasn't the most user-friendly solution for the rest of the family. The issue suggests a larger trickle from the battery than there should be, but it's not worth my time or money to figure out what device is pulling current even when the key is off. So the solution was to get a simple switch that does the same thing as physically disconnecting from the terminals. It's worked great so far; no battery drain after leaving the boat for a month. Originally I intended to mount it below the dashboard, but I ended up taking more simple route and mounted it closer to the battery in one of the compartments under a back seat. I used a 3 5/8" hole saw to cut through the plastic wall of the seat, about halfway up from the floor. Then I pushed the switch into the hole, marked the four locations of the bolts, drilled four small holes, and mounted the switch with four nuts and bolts. NOTE, I needed the following extra materials to install the switch: 1. 3 5/8" hole saw (not needed unless flush-mounting, and you could use a different tool too) 2. Four bolts and nuts (at least 3.5" in length, I forget the diameter) 3. Wire and crimp-connectors to extend the wire from the battery to where I mounted the switch, remember that you only need to extend the positive (+) cable to the switch)
C**L
I almost bought the "other one" but so glad I didn't. This switch is great for my boat.
First thing I did when I bought a boat is install a second battery because a dead battery on the water is both likely, and extremely problematic. Or worse. If you've shopped for marine battery switches you've seen the "other" brand. The big round, surface-mounted one. Then you see this one and think, "it's just so small" or "how does it mount to my boat?" I took the leap of faith and couldn't be more pleased with the results. My first consideration was accessibility. I didn't want the switch to be buried inside a compartment that would make access difficult while on the water. That way I could easily switch between batteries when we're fishing, using the downriggers and playing music, and back to when we're running the main engine. The smaller size and flush-mounting capability of the Blue Sea switch were definite advantages in that regard. My other consideration was the power handling capacity of the switch, especially because of its smaller size. A quick look at the published specs shows continuous, intermittent and cranking ratings of 350A, 600A, and 2,000A respectively. Way more than needed for my application. Another bonus is the "make before break" design that keeps all of my electronics alive as I switch between batteries. I never switch with the main engine running. I invested another 10 bucks in a hole saw and drilled a hole in the battery compartment facing the cockpit, then installed the switch flush to the carpeted front face. Bolted it in with new stainless hardware, terminated the batteries and not only is it functional, but it also looks great. No telling about long-term reliability at this point, but I'm glad I opted for the built-in look and accessibility of this switch.
B**N
Great product
this product worked great. Super easy to install. I needed a disconnect on my boat since i was having a parasitic draw on the battery. It is installed in the elements and is still holding up great
S**O
Missing nut :(
R**.
Quality Item, but expensive for what it is. Bolts require 10mm Cable Lugs for attachment.
V**L
Prodotto di qualità
A**N
Quality you can feel. Note: Not the same mounting holes pattern that the older version.
D**A
Provato con corrente di 100A e non diventa neanche tiepido. E' tutta un'altra cosa dagli stacca batteria cinesi. Anche le dimensioni sono monto abbondanti. Ottimo