Welcome

Power Management

House Battery

The A'van Applause 500 motorhome is currently fitted with a single 12 V 120 Ah deep cycle battery (see 12V electrics for more detail). Battery voltage and instantaneous current drain are monitored by a purpose-built digital panel meter; state of charge (loosely defined) is monitored by a kit-built battery amp-hour meter.

Elektroblock EBL 269-2

The 12 volt power in the Applause is distributed and controlled by a Schaudt EBL 269-2 "Elektroblock" management system. The Elektroblock charges the battery and supplies 12 V appliances with power. It consists of:

  • The 18 A LAS 1218 charger module
  • The 12 V distribution
  • Fuses for the 12 V circuits
  • Other control and monitoring functions.

A full description of the EBL 269 is provided by Schaudt, and some detail, including circuit diagram, is repeated here for the Applause.

The Schaudt philosophy appears to be to separately fuse each major electrical item. However, as received, A'van had wired the side step into the water supply circuit, controlled from the Switch Panel, and the aftermarket solar cells and controller were wired independently of the Elektroblock.

Control Panel

The control and switch panel is a Schaudt LT400.

Characteristics:

  • Eight-step voltage indication of house and starter batteries
  • Optical battery alarm in case of a great drop in voltage of house battery
  • Four-step indication of water tank fill levels for fresh and grey water tanks (red, yellow and green LEDs)
  • 12 V main switch with indicator
  • 230 V mains-on indicator

Solar Power

The Applause came with two 80 Watt solar panels fitted to the roof (see photo of the roof) and are presently managed by a MorningStar ProStar PV Charge Controller model PS-15M. Features include:

  • Rated charging/load current 15 A
  • PWM Charging with 3-stage Charge Control (to allow battery be left unattended for long periods)
  • Battery voltage sensing
  • Battery temperature sense via fitted Remote Temperature Sensor
  • Overcharge, Over-discharge and Over Temperature Protection
  • Informative LCD Display and LED indicationw of system and battery conditions

A third, 85 Watt, foldout panel has been added to increase the solar charging for longer bush camping. See how here.

Sizing the Electrical System for the Applause

Given some experience in bush camping with the Applause, and all the changes I have made, what can be concluded about the adequacy of the present electrical system?

1. Estimate the expected load/usage. The compressor fridge is the dominant load, and I have done all I can about that. Other uses such as TV and lights and such add up but are not large. To help me test my estimates and relate them to experience, I used Richard's Solar Spreadsheet. The State of Charge Meter shows a total night (ie, no sunlight) consumption of approximately 35 Ahr.

OVER A 24 hr DAY Total Ah Night Ah
Fridge 49 20
Lights 4 4
Radio,TV 8 7.7
Pumps, … 2 1.2
TOTAL 63 33

2. Sizing the Battery. I need a battery that can supply the whole load for at least 24 hours in case there is no useful sunshine for a day or so. The maximum Depth of Discharge generally should be about 70% for long battery life, but for this rare condition a DoD of 50% may be acceptable. So for one day only, Battery size > 63/0.5 > 126 Ah. So the 120 Ahr Battery I have in the Applause is the minimum size. Better would be two x 120 Ahr batteries.

3. Sizing the Solar Panels. The solar panels need to be able to replace the night discharge from the Battery and supply all the daytime load. So Solar supply > 63 Ahr over 24 hours. Assume Peak Sun Hours available is 4 (kW hr/m²) for our locality, on average. This is everywhere north of Perth or Sydney in the Winter, everywhere in Australia in Summer. Then 63/4 =15.7 A. From my experience, an 80 Wpeak panel can give out up to 4.5 A to the Battery, so three 80 W panels are not quite enough. In Winter in Melbourne, Peak Sun Hours is about 3. For solar panels to fully supply the load we would need five 80 W panels.
The Solar arrangement is likely to be problematic for extended bush camping.

4. Battery Charger. This should be sized to supply ~C10 and no more than C5 of Battery capacity. So, for 120 Ah Battery, it should be ~12 A and no bigger than 24 A maximum current.
The Elektroblock 18 Amp charger is a good size.

Mains Power

A permanently attached heavy duty 15 Amp mains cable 15 m long is accessed via a hatch near the rear on the driver's side. It connects through two Load Balance detectors to two power points under the bed (one for the Elektroblock and the other to other power points in the Applause.

Mains powered equipment include:

  • Truma Hot Water Service, which can use LPG and/or 240 Volt
  • Dometic Roof Air Conditioner
  • Sharp Microwave Oven
  • Digitor LCD TV (which also works fine on house battery)
  • Philips HTS3105 6 speaker DVD/CD/Radio home theatre system (which works fine on a 150 W MSW inverter).

Some detail, including various changes, are given in other pages.

LINKS

Electrics

EBL_269-2.jpg (98 kB)

The Schaudt electrics manager. An 18 Amp battery charger is built in.

LT400_pic.jpg (60 kB)

Control and Switch Panel for Applause 500

PV_controller.jpg (30 kB)

Prostar Solar Power Controller for Applause. Battery temperature sense wire, power point wired to Controller, insulated Water Heater.