Truma SDC 10/20 Solar Dual Battery Charger
Official technical documentation and workshop diagnostics for Solar Charge Controller.
View official manual on manufacturer's site ↗Technical Specifications
Battery TypesGel, AGM (Absorbed Glass Mat) or liquid electrolyte, 12V (24V) lead-acid, 50-100Ah (SDC 10) or 50-200Ah (SDC 20)
Not Suitable For6V batteries, non-chargeable batteries, nickel-cadmium batteries
Battery Type SettingSet for battery 1 only (battery 2 assumed same type): 1 = Gel (pre-setting), 2 = AGM, 3 = Liquid (liquid electrolyte).
Charging Current DistributionSettable split between battery 1/battery 2, from 0 (0%/100%) to 9 (90%/10%) in 10% steps; pre-setting is 5 (50%/50%). Once battery 1 is fully charged, all charging current is fed to battery 2 regardless of the set value.
Pwm Charging Frequency0 = 25Hz (pre-setting), 1 = 50Hz, 2 = 100Hz - adjustable to reduce possible interference.
Battery 2 ScalingOn 24V systems, double the 12V values shown to work out the 24V equivalents.
Control Panel Reference
- H1 Function display LED - battery 1
- H2 Function display LED - battery 2
- H3 Battery type LED - AGM, gel, liquid
- H4 Charging current distribution LED
- H5 PWM charging frequency LED
- H6 Numeric display - shows the values of H3, H4, H5
- T Query/change operating mode button
- B2 Internal temperature sensor
- X1 Connection for external temperature sensor B1
- X2 Connection for battery 1
- X3 Connection for solar module
- X4 Connection for battery 2
- X5 Connection (RJ-45) for optional remote display
Master Troubleshooting & Diagnostics Matrix
| Error Code / Indicator | Symptom / Meaning | Step-by-Step DIY Fix | Suggested Actions |
|---|---|---|---|
N/A | LED H2 flashes (the source document's own troubleshooting table labels this as the battery 1 status LED - see the reference diagram below, whose own panel legend labels H1, not H2, as battery 1's LED; this is an inconsistency in the source material, not a transcription choice) Possible Cause: Poor or incorrect connection between the device, the battery, and the solar module. | Check connections from the device to the battery and solar module, ensuring they are connected to the right terminals. Test the fuse, solar module and battery. | DIY Safe |
N/A | LED H2 flashes in longer intervals (see the symptom note above on the H1/H2 labelling discrepancy) | This is normal - the battery is fully charged, no action needed. | DIY Safe |
N/A | LED H2 shines steadily (see the symptom note above on the H1/H2 labelling discrepancy) | This is normal - the battery is being charged, no action needed. | DIY Safe |
N/A | LED H2 flashes in short intervals (see the symptom note above on the H1/H2 labelling discrepancy) Possible Cause: The battery is not being charged. | If necessary, replace the faulty battery. | DIY Safe |
N/A | LED H2 does not shine at all (see the symptom note above on the H1/H2 labelling discrepancy) Possible Cause: Battery not connected, or over-voltage. | Check the battery connection and check for over-voltage. If this does not solve the problem, contact Truma Service. | DIY Check / Tech Fallback |