P-Bus Energy Shunt SHX 300-L

The P-Bus Energy Shunt SHX 300-L from philippi is a digital current measuring shunt for installation in the negative line of a charging source or a consumer. It complements the P-BUS energy monitoring of yachts and motorhomes with its own measuring point and records continuous currents from 10 mA to 300 A — with galvanically isolated bus connection.

• Precisely detects even the smallest currents from 10 mA up to 300 A continuous current
• Makes the real yield of a source visible — even during hours of low performance
• Galvanically isolated P-BUS connection — also suitable for circuits separated from the on-board network
• Easy retrofitting to solar cells, wind generators, alternators or consumers without their own P-BUS interface

Resolution: why 10 mA count in yield measurement

An energy shunt answers not a momentary question, but a cumulative one: What has this source delivered over the day, what has this consumer drawn over the week? For this sum to be accurate, the lower part of the range must also be precisely recorded.

The philippi SHX 300-L starts at 10 mA. For a solar system, a significant portion of the yield does not occur in full sunlight, but is distributed over hours with diffuse light. For a consumer, it's the opposite: the standby component is small, but runs around the clock. In both cases, the relevant quantity arises from many small values — and a shunt with a coarse lower limit will exclude them from the balance.

Use in P-BUS energy monitoring

In philippi's P-BUS energy monitoring, the system monitor — such as PSM3 or PSL — displays the complete energy balance of the DC on-board network: Which source supplies how much current, which consumer draws how much power? Chargers of the ACE series, charge boosters of the DCB series and solar charge controllers of the SCE series already supply their data via the P-BUS. For all other DC power sources and DC consumers without their own P-BUS interface, an SHX 300-L is additionally installed — this allows the yield of a solar system or the consumption of a single device to be recorded separately.

The power supply is connected via a plug-in terminal, the power connection via an M8 connection bolt, and the connection to the P-BUS via the M12-T connector.

Compatibility

The SHX 300-L is part of the philippi P-BUS system and works with the PSM3, PSL and PSL Plus system monitors. For battery monitoring itself — i.e., for charge status, starter battery voltage and battery temperature — the Battery Management Shunt SHX 348 or SHX 648 is used; the SHX 300-L operates alongside it and does not replace it.

Frequently Asked Questions

What is the SHX 300-L used for?

For installation in the negative line of a charging source such as a solar system or a consumer without its own P-BUS interface, for additional current measurement in P-BUS energy monitoring.

Why is measuring from 10 mA important for yield measurement?

Because the relevant quantity arises from many small values — solar yield in diffuse light, standby consumption around the clock. A shunt with a coarse lower limit will exclude these components from the balance.

Does the SHX 300-L replace the battery management shunt?

No. For charge status, starter battery voltage and battery temperature, the Battery Management Shunt SHX 348 or SHX 648 is used. The SHX 300-L additionally measures a single source or a single consumer.

Is an existing P-BUS system required for operation?

Yes, the SHX 300-L delivers its measurement data to a P-BUS system and complements the energy flow detection there, displayed for example on a PSM3 or PSL system monitor.

How high can the current be for a short time?

Briefly, 600 A for 1 minute or 1500 A for 0.5 seconds are permissible, with a continuous current of 300 A.

If you have any questions about integration into your P-BUS system, we will be happy to advise you — order now.