Sharing power between ports

Six ports at 100 W would need a 600 W supply. Most setups never draw that much at once, so Power Manifold can run from a smaller supply and divide its power between the ports. You tell it how much power the supply has (the budget) and which ports matter most (their priority).

The budget

Set the Chassis budget in the web interface’s Settings or in Home Assistant. Use your power supply’s rating in watts, or a little less. The default is 360 W.

When a device plugs in, it agrees on a voltage and current with its port, for example 20 V at 3 A. Power Manifold sets that much power aside, 60 W in this example, even if the device draws less at the moment. Laptops and other devices can jump to their full power at any time, so setting aside the full amount is what keeps the supply from being overloaded.

A port with a blade but nothing plugged in sets aside 15 W, enough for a device to plug in and start at 5 V.

The web interface shows both numbers on each port’s card: the large figure is what the device uses right now, and the contract under it is what is set aside for it. The budget bar at the top adds them up for the whole chassis.

When there isn’t enough

If a newly plugged-in device would take the total over the budget, Power Manifold makes room:

It turns down lower-priority ports, starting with the lowest. It never takes a port below 15 W.
If that isn’t enough, it gives the new device whatever is left.

A port that has been turned down keeps powering its device, only with less power. Its light pulses slowly, and its state shows throttled. The device sees a new, smaller offer and switches to it without disconnecting.

Nothing is switched off to save power.

When power frees up, for example when another device is unplugged or a port with switch off when charged turns itself off, the turned-down ports get it back, highest priority first. A device that has finished charging but stays plugged in keeps its share, because it can start drawing again at any time.

Priorities

Each port has a priority from 0 to 255, where 0 is the most important. By default a port’s priority is its port number, so port 1 is the most important and port 6 the least.

Ports with the same priority never take power from each other. The one that plugged in first keeps what it has.

Set priorities in Home Assistant (a number for each port), over MQTT or with the HTTP API.

Example: a 150 W supply powers four Raspberry Pi 5s on ports 1 to 4, which take 25 W each, and a 100 W laptop on port 6. Give the Pis priority 0 so they always get what they ask for, and leave the laptop at 6. The Pis take 100 W of the budget, so the laptop is offered the rest and charges more slowly. If a Pi is unplugged, the laptop gets its share.

When the input voltage drops

If the supply voltage falls below 20 V, every port is limited to 3 A (60 W at most) until the voltage has been above 20.5 V for 30 seconds. Devices are offered less, but nothing is switched off. While this is happening the web interface and Home Assistant show a problem saying the ports are capped.

If you see this often, your supply is too small for your devices, or its cable is too thin. Lower the budget or use a bigger supply. See Troubleshooting.

The fan

The fan switches on automatically under any of these conditions:

when the total power reaches 80 W, staying on until it falls to 60 W;
while any port delivers more than 3 A;
while any blade’s converter is at 65 °C or hotter, staying on until all of them have cooled to 55 °C.

You can change the first two rules in Settings, or force the fan on or off from the web interface or Home Assistant.