What you need

Electrical equipment

Depending on the components you want to install, you’ll need some basic electrical equipment such as a soldering iron, a crimp tool and related connectors, shrink tubing, wire cutters, and a multimeter.

Computer and Internet access

Having access to the Internet is only required to download module updates. These will appear in the Downloads section on this site. Once you’ve downloaded an update you’ll then need to upload it to the HQ. A laptop or desktop computer will be fine for this.

Web browser

To access the HQ you need a browser. There are no apps to download, no software to install, you simply need a browser. But not just any browser, you need an HTML5-compliant browser.

Browsers we know will work are FireFox (any recent version above about 55 or so), Chrome (again, any recent version, such as 63.*), Safari (11 on Mac OS X or newer will do fine as does any recent version on iOS.)

A browser we know will not work properly for all functions is IE 11 running on Windows 7.

If you’re not using one of the known good browsers then check your browser window against the screenshots that will follow. A good place to start checking is the traffic light (on the left, below the menu bar and status panel): it should always show at least one colour, so if it shows an empty outline of four boxes you will need to use a different browser.  Our preference is for you to use the most recent version of either FireFox or Chrome.

The browser can run on a PC, laptop computer, tablet or smart phone as long as the device can establish a WiFi connection and supports HTML5/CSS3.

How to wire the modules

Here’s an overview of where to place the BC modules within your boat.

Installing and powering up the modules

The first module to power up is the HQ. Once this is powered up and you’ve connected to the SharksHead web interface you can proceed to power up the other modules. You want to pick a central and dry spot on your boat to maximise the reliability of the wireless communication from the HQ to the modules as well as to your web browser. On most boats the area around the navigation table would be an obvious choice. You don’t have to screw any module into some bulkhead, though. We provide some hook and loop tape (aka Velcro) as a temporary or medium term mounting option.

Powering up and connecting to the HQ

Before powering the HQ, ensure that the switch on the enclosure is set to the “AP” setting, which means it provides its own WiFi access point for this setup.

The HQ takes its power from a 2.1 mm (diameter of the inner pin) barrel jack, the plug  is included in the kit. This is a centre-positive jack, so connect your bus positive to the red wire and bus negative or ground to the black.

Important note: The HQ should be left running at all times in order to be able to store the sensor information and react to events. Therefore, we would recommend to either:

  • wire the HQ directly to a house battery with an inline fuse close to the battery (the HQ will only draw about 200mA on average, so a 1A fuse would be sufficient) or at some other convenient point before the main battery switch, or
  • wire it to an existing breaker panel switch or a dedicated breaker switch and then leave the main battery switch on at all times (except for maintenance work on the bus itself) while turning off other devices at the breaker panel, therefore leaving the HQ powered on when leaving the boat

Apply power to the HQ, then wait a  minute or so as it boots. Go into your WiFi setup and scan for available networks. If things are working properly you’ll see “SharksHead” in the list, then select it. The SharksHead password is composed of the four characters


followed by the last four digits of your HQ serial number. For example, if your HQ serial number is 187-944-8199 then the password will be shap8199. That’s “shap” as in “SharksHead Access Point”, not “shark”.

Next, from a browser enter the URL:

with the http:// prefix. You can then bookmark it, if you want.

This will take you to the Setup page of the SharksHead web interface.

Here’s a quick overview of the web interface. Along the top left are the links that take you to the various pages making up SharksHead. Setup is the last on the right-hand end. At the top on the right is the login status, which for you will show Read-only and a Login link.

Below that, showing information on the left-hand side of the page and the right, is the mini status panel, which, for you, now, will be empty because you haven’t yet started any modules. The status panel is updated in real-time, as are many other parts of the SharksHead web interface. Don’t worry about this at the moment. As you add modules this will start to show data and make more sense.

Below that on the left is a stacked set of boxes, the bottom one shaded green. If this is not green then you have a browser problem; see the browser comments above. This set of boxes is called the traffic light, despite the fact there are four lights, and it is also updated in real-time. This is one of the ways you are alerted to problems SharksHead has detected. Again, this won’t make much sense until you have your modules up and running for a while.

To the right of the traffic light is a grey area where you interact with whatever page you’ve selected.

If you’ve gone to some other pages for a look-see, come back to the Setup page and select the General tab. Once you set up things here you will rarely visit again.

First thing to choose is the language. At the time of writing only the UK and US English and German languages are complete. The others are partially complete so you will most likely see a lot of UK English, being the default when no translation exists.

Following on down from there you can select your number format, units, air pressure units and status panel style. All these options are stored in a cookie on your browser so if you access SharksHead from multiple devices you’ll need to set these on each device.

Next, setting your timezone. To do this you’ll need to log in. There are two log in states, being Read-only and Administrator. When you are Read-only you can only change cookie-based options. These are the options on the Setup-General page plus various options sprinkled throughout the other pages. To make configuration changes to HQ or any module you must be logged in as Administrator.

The Administrator password is composed of the 5 characters


followed by the last four digits of the HQ serial number, similar to how the WiFi password is defined.

Log in as Administrator and come back to the Setup page and select the Timezone tab. Select your region, another pull-down menu will show, select your location (and in some cases a third drop-down will show).

When you’re happy hit the commit button. After a short moment your browser will lose connection to the web site; wait a couple of seconds and reload the page.

What if I have my own WiFi?

You may leave the HQ in Access Point mode (switch in the “AP” position) from here on, however, if your boat already has a WiFi router (acting as an AP) then you can reconfigure HQ so it joins your WiFi as a client. Do this in the Setup-WiFi tab.

Simply choose your SSID from the list, or type it in if it’s hidden, enter the password, and hit the OK button.

Next, flip the enclosure switch to the “CL” position, wait a minute or so while the HQ reboots, then check your WiFi router settings to see if the HQ has appeared on your WiFi network. If it has, great, you can continue by accessing it through your WiFi by using the IP address your router has assigned to HQ, e.g.

If it hasn’t then your only recourse is to set the switch back to “AP”, wait a minute or so, connect to the SharksHead SSID and recheck the settings in the Setup-WiFi page.

The HQ only supports 802.11b WiFi. Please ensure 802.11b is enabled on your router.

Preparing to power up the other modules

Getting the other modules going requires two steps, powering each module and entering their serial numbers into the HQ. These steps can be done in any order, however, this entire process, called enrolment, will proceed a little quicker if you enter all the serial numbers first. So that’s what we’ll do now.

Go to the Modules page and select the New module tab. Enter one module’s serial number and hit the OK button. Repeat for the other module serial numbers.

At this point you’re finished with the web interface part of enrolling modules. To watch the rest happen in real-time, select the In progress tab and stay on that page. The list shows you info about the state of each module’s enrolment process. When a module has completed enrolment the status will show Operational for one minute and then the module will disappear from the list. So that’s what to look for as a sign of success, either a status of Operational or the module not appearing in the list. If things are working well each module will complete the enrolment process in a matter of seconds.

If you’re curious about what happens behind the scenes during this process, select the full status panel. I won’t go into details here but the full status panel displays more of the enrolment steps in real-time. You have to be eagle-eyed, though, because it all happens pretty quickly once it starts.

Powering up the TPH module

The first module we’ll power up is the “temperature, pressure and humidity sensor.” For now power it with AA batteries, so unscrew the lid and pop in a couple, taking heed of their orientation. You can leave the lid off for now, too, as we will access the 6-pin female header later.

The LED on this and all other modules gives you feedback about its health and network state. The states and their LED patterns are

Red, SOS in Morse codeModule is damaged
Amber, 1 flash sequencePairing
Amber, 2 flash sequenceConnecting
Amber, 3 flash sequenceEnrolling
Green, solid for 1 minuteFunctioning

If you see SOS it means the module is damaged and will not function. It will show SOS for one minute then turn itself off. Please contact our support if this happens.

The first time you power up a module it will go through each of the amber flash sequences and finally to green. Green, or functioning, is where you want to be.

A quick discussion about the way the network operates is in order. SharksHead modules use the 2.4GHz (same as WiFi) radio band to communicate. They aren’t WiFi clients, you can’t talk to them via WiFi, they use the same band because they need to legally work worldwide. In order to get good, clear communications between the modules we have to do a bit of a tap dance around the more powerful WiFi transmitters. Each time the HQ boots up it scans a list of frequencies within this band and selects the one that has the least amount of traffic or noise, then it starts using that channel.

Each module has the same list, and when it boots (or loses connectivity) it continually scans these channels until it finds either the HQ or any SharksHead module. This scan is done in the Pairing and Connecting states, so if you see the amber 1 or 2 flash sequences you know it’s scanning the channel list looking for other modules. A scan may complete in a couple of milliseconds, if it finds a module at the beginning of its scan, or may take up to a couple of minutes.

The moral here is not to be worried if you see the amber flash sequences. Anything longer than 5 minutes and you could have a network connectivity problem. I talk about how to sort this out in the BC section below.

Back to the TPH. By now, hopefully, it will have enrolled. After a few minutes you’ll start to see changes to the web interface. The status panel will show temperature, pressure and humidity values, the module will appear in a couple of drop-down menus (Modules, Control), you’ll get to see graphs on the Environmentals page, you’ll begin to see network stats in the Modules-Network page, messages will appear in the Messages page, and the Dashboard will have a couple of objects, gauges in this case, you can play with. Try the Edit button at the bottom left of the Dashboard page.

The barometric pressure sensor likely needs to be calibrated. This can be done from the Modules page by selecting the TPH module from the drop-down menu and clicking the calibrate link under Functions, then entering the pressure from a known source, e.g. your existing on-board barometer or a nearby weather station.

If you’re running a TPH Model 1 of any version, or a Model 2 version 0.1, then you must wait 5 to 10 minutes before the module will begin sending accurate values back. However, if you’re running a Model 2 version 0.2 or later then as soon as the module receives the new calibration it will send accurate values back with its next transmission.

Here’s a screen shot:

One final thing to do is give this module a label, a name if you will. When a module is enrolled it’s given a unique module number, starting from 1, and the web interface will show the module’s name as, for example, “Mo 1.” Adding a label will extend this name and make it more meaningful. From the Modules page select this module from the drop-down menu (Modules-{mo} from here on,) then hit edit label and give it any label you like. For the TPH module there aren’t that many useful labels other than “TPH,” so I’ll forgive you if that’s what you choose (that’s what I chose,) but for the other modules this label can be more descriptive, such as “Cabin lights” or “Battery #4 aft starboard.” Doing this will change the module’s name to, for example, “Mo 1 – TPH.”

Powering up the CC

Next on the list is the CC. The CC is placed in line to any 12VDC consumer, like a radio or some lights. Anything that draws 8A or less. You pick your consumer, cut its power cable and strip the wires, remove the CC’s lid and secure the wire ends in the terminal block, taking note of which wire goes where, “IN” referring to the bus, and “OUT” referring to the consumer. The positive wire is on the left of each pair when looking at the terminal block. So from left to right, the wires are: Bus: plus – minus, then your device: plus – minus. As soon as it gets power from the bus it will start its enrolment process.

The black button on the CC has multiple functions. When pressed for less than 2 seconds it acts as an on/off switch for the consumer, the LED showing green momentarily if it was switched to on and red if switched to off. When the button is pressed for longer than 2 seconds the LED shows you whether the switch is on or off (green or red) without changing the switch.

And just to complicate things a tad, if you’ve turned “locate” on for the CC from the Modules-{mo} page (which turns the LED blue,) then hitting the black button turns locate off without changing the switch status. Locate is useful to quickly identify a module if you have several modules of the same type next to each other or you’ve forgotten where a module is.

You also have access to the on/off switch and the virtual circuit breaker from the web interface, on the Consumers page and the Dashboard.

The red button restarts the CC.

Powering up the PG

The programmer is the simplest of all the modules. Plug the PG cable into the TPH’s 6-pin header (it only goes in one way.)  The PG doesn’t have a LED so you’ll have to watch the Modules -> In progress page to see how things are going, or, if you have keen eyesight, you will see a small antenna in the top left corner of the PG display that shows “radiation waves” representing the network states.

Once the PG is enrolled you can remove it from the TPH header and store it somewhere safe. It doesn’t need to be powered on all the time. You’ll only use the PG to upgrade modules.

Powering up the BC

Last on the list is the BC. The BC is between (or in series with) your battery positive and your bus positive posts. It has a battery positive nut and bolt, a bus positive nut and bolt, a battery negative lead, and a battery temperature sensor on a lead.

Install the BC on top of or alongside the battery you want to monitor and control. After turning off the master battery switch (if you have one), disconnect the existing battery positive cable from the battery post and attach it to the M6 bolt marked “BUS”. The bolt has a diameter of 6mm or 1/4″, but an 8mm or 5/16″ ring terminal will fit as well. If your battery has round terminals an adapter will be required.

Then connect a cable to the BC terminal marked “BAT” and attach it to the battery positive terminal (where your original battery cable was a moment ago). You can source this extra cable from us if required.

Make sure the contact surface between the cables and the contact or terminal on the BC is clean and flat to maximise the contact area (which minimises heat and hence power loss). The flanged nuts on the BC are M6 and require a 10mm wrench or shifter. Make them snug but there is no need to overtighten the nuts (though nothing will break if you keep tightening, just the bolt itself will start turning as well).

BC posts view

BC posts

Do not put any stainless steel or other washers between the ring terminal on the cable and the ring terminal from the BC, as this will increase the resistance and heat up of the bolt and cause a power loss in your system.

Note that the BC has an internal temperature sensor and will turn itself off if the temperature on the terminals is unsafe.

To finish it off,  attach the external temperature sensor (not shown in the photo above) to the battery (with sticky tape, duct tape or blu.tack, perhaps), ideally with the sensor chip (the square protrusion under the shrink-wrap) against the battery.

As soon as the BC has the battery negative and either of the positive connections it will start its enrolment process.

If there are possible network connectivity issues contacting the HQ, this is likely where you’ll encounter them. If the BC shows any amber flash sequence, especially the one flash sequence, for an extended period of 5 minutes or more, you want to switch to Plan B:

  • Remove the BC from the battery, take it back to the TPH module,
  • pop the BC’s lid by removing the four black rubber pads to access the Philips head screws, and
  • use the 5-pin 2-wire (power) cable from the kit to connect the BC’s 6-pin header to the TPH

It should then complete its enrolment and show a green light for one minute. Disconnect it from the TPH and put the lid back on, being careful not to catch any wires between the lid and the enclosure body. Enrol your second BC the same way.

Then install the BCs back on their batteries. But we’re not done yet. The BCs can’t contact the HQ from where they are, so this is where the TPH’s relay functionality comes into play. You need to position the TPH module in a location where it can contact both the HQ and the BC’s.

First, enable some network diagnostics. Go to the Modules page and select the TPH module from the drop-down menu, then hit network test. The TPH LED should start flashing blue twice a second. You do this so you know when you’ve taken the TPH out of network range of the HQ, as the flashing becomes erratic or stops altogether.

Then turn on the network test for one of the BC’s. Now it’s a matter of placing the TPH module somewhere, leaving it for about 5 minutes, and checking to see if the BC’s LED is flashing blue. If it is, great, you’ve found the TPH’s final resting place. If not, move TPH and try again.

Things to avoid are large metal structures, such bulkheads or doors, between the TPH and the BC’s. People are also pretty good at blocking these radio signals, too. Wood, glass, plastic, smaller objects are generally fine. Line of sight is best but rarely possible.

If you just can’t find that right spot for the TPH and you suspect there’s just one more corner you need to negotiate then you could try using the CC as well. It, too, has relay functionality so you could try for a two-hop solution. And you can also move the HQ around to different locations, too.

Once (if) you can get your BC’s connected you can then turn the network tests off by hitting the network test link again on both Modules-{mo} pages.

Now the BC’s are enrolled and you’ll start to see their data feed on the web interface. You’ll have voltage and current displayed in the status panel, graphs in the Storage page, and several gauge and relay (the relay in the BC, not a network relay) objects in the Dashboard.

The BC Dashboard gauges can be a little daunting because there are so many to choose from, but it all boils down to this: there are bus voltage, battery voltage, current and power gauges for each BC, each one showing the BC’s label if you’ve set one or its Mo number if not. There are also bus voltage, current and power gauges labelled “HQ” which show aggregate values, in the case of voltage it shows the average bus voltage from the BC’s, current is the sum of the currents from the BC’s, and, likewise, power is the sum of all the power from the BC’s.

Another detail to note is the current’s sign. We’ve defined positive current to mean current is flowing into the battery, and negative as flowing out.

Finishing with the TPH

Once you have all the modules enrolled you can pop TPH’s lid back on, decide how to power it, and decide on its power saving mode.

Ideally you will power the TPH from the 12V bus by attaching the bus positive to the red lead of the barrel connector jack and bus negative to the black. Powering it this way is a set-and-forget option. Definitely our preference.

However, you may power the TPH from AA batteries, either Alkalines or rechargeable NiMH’s. This gives you greater flexibility in the placement of the TPH, especially if you’re using it as a relay for your BC’s, but it does come at the expense of changing the AA’s. If you are using the TPH as a relay then you cannot enable its power saving modes, and so your AA’s might only last a week or so because the module must run continuously in order to provide relay functionality.

If, on the other hand, you do not need to run the TPH as a relay you can enable its power saving mode. To enable power saving mode, go into the Modules page, select the TPH from the drop-down menu, hit configure in the Options section, and you’ll see a page like this:

This is the default setting, with both Radio relaying and the LED enabled. Change this by selecting Low power and turning off the LED:

and hit the OK button. This sets the TPH to its highest power saving mode. In this mode a fresh set of Alkalines might last up to 12 months, or a good set of fully charged eneloop’s might last up to 9 months.