Charger
Renogy DCC30S (legacy) wiring diagram
Charge a house battery from the vehicle and solar using the legacy DCC30S. Match the four physical studs and check the model’s 25 V solar limit.
- Compatible systems
- 12 V
- Rated output
- 30 A
- PV open-circuit limit
- 25 V
Connection essentials
Map the positive studs
ALT + and START + both represent the same physical ALT+ stud. BATT + connects to the charger’s OUT+ stud.
One common negative
The power circuits share one NEG− stud. Connect negative first, then house positive, starter positive and finally solar positive.
Check the model and IGN
Confirm the legacy part number and 25 V PV limit. Connect IGN for a smart alternator; leave it unconnected for traditional alternators.
Wiring diagram
How the DCC30S is wired.
This legacy DCC30S example connects the starter and house banks. Solar, IGN and sensing are not drawn. Match its 25 V PV limit and shared NEG− stud to your exact model.
Legacy DCC30S vehicle-only example: 1 m battery runs, 6 mm² cable, 45 A input and 40 A output protection. These follow the Version 1.1 DCDC30 table; the input fuse applies to ALT+, not PV. Solar, IGN and sensing are disconnected. Confirm your full model number before using these values. Manufacturer installation manual
Edit this wiring exampleHouse-bank output sizing for this example
The example uses the vehicle input only. Solar, IGN and sensing are disconnected; follow the legacy manual to add them.
1 m one way
12 V system
- Wire
- 6 mm² · 10 AWG
- Example fuse
- 40 A
- Design current
- 30 A
- Voltage drop
- 1.5%
Sized against ABYC E-11. The design current is the unit's rated output. The length is one way; voltage drop includes an equal-length return.
Run-length and manufacturer assumptions
The editable example uses 3.048 m (10 ft) runs unless a shorter run is stated. Metric overviews round these to 3 m. Adapt the parts and lengths to your installation before choosing cable and protection.
Legacy DCC30S vehicle-only example: 1 m battery runs, 6 mm² cable, 45 A input and 40 A output protection. These follow the Version 1.1 DCDC30 table; the input fuse applies to ALT+, not PV. Solar, IGN and sensing are disconnected. Confirm your full model number before using these values. Manufacturer installation manual
Supporting parts
- 2 m total of 6 mm² (10 AWG) marine cable
- Terminations for 6 mm² cable, matched to the equipment's screw terminals, leads or studs
- 40 A fuse and holder on the positive run
- Heat-shrink, strain relief and terminal boots sized to the cable
Check stud sizes, fuse type, run length and how warm the space gets against the gear you actually have before you order.
Installation notes
Before you install.
Open a question for model-specific guidance and sources.
Reviewed against manufacturer family documentation (rev. Version 1.1), checked 2026-10-01. Exact variant details still require confirmation. Manufacturer documentation →
Does this page match my DCC30S?
This page covers the legacy DCC30S / RBC30D1S-G1 family with a 25 V PV limit. Renogy has reused the DCC30S name for products with different solar limits. Confirm the full part number before using these notes or a newer manual.
The archived Renogy Version 1.1 manual specifies a 12 V house battery, up to 30 A charging and 400 W maximum solar input. Its technical table limits PV voltage to 25 V, including cold-corrected array Voc. The 25.5 V protection trip does not increase that design limit.
Which diagram labels match the charger's four power studs?
The physical charger has PV+, ALT+, OUT+ and one shared NEG− stud:
- PV + → PV+: solar positive.
- ALT + and START + → ALT+: two diagram labels for the same starter-battery input, not independent sources.
- BATT + → OUT+: house-battery positive.
- PV − and BATT − → NEG−: one common negative connection, also serving the starter-battery return.
IGN, temperature sensing, battery-voltage sensing and RS485 are outside the drawing. Match the unit's physical labels before connecting.
What is the connection order, and do I need IGN?
Follow the manual's sequence: NEG− first, then house positive, starter positive and finally PV positive. Check polarity before connection.
Smart alternator: connect IGN to the vehicle ignition circuit as the manual specifies. Traditional fixed-voltage alternator: leave IGN unconnected. Check the alternator type with the vehicle manufacturer if it is unknown.
What protection and cable information is verified?
The DCDC30 row specifies 45 A vehicle-input protection and 40 A charger-output protection. Its cable guide gives 10–8 AWG for 1–5 m and 6–4 AWG for 5–9 m; select within that guidance using actual current, ampacity and voltage drop. These are separate protected battery circuits.
Terminal torque remains unresolved. The manual's 16 N·m / 3.3 ft-lb values are inconsistent; confirm the correct revision with Renogy rather than choosing either number. The technical table identifies M8 terminals.
Can solar and the alternator charge at the same time?
Yes, but they share the 30 A total charge limit. Either source alone can supply up to 30 A; when both actively charge together, the legacy manual limits each to 15 A. Solar can also maintain the starter battery at the appropriate house-battery charge stage.
Select the battery chemistry deliberately. The legacy Li profile uses 14.4 V boost, without float or equalization. Keep the charger dry and ventilated, and verify battery/BMS temperature permission; do not assume newer firmware behavior applies to this unit.
Fit check
Connect it to the rest of your system.
Describe your setup to draft a system with DCC30S connected. Review the selected parts and cable lengths, then edit the diagram in Crimp.
The model only picks parts and draws the connections. Every wire size and fuse rating still comes from Crimp's own sizing, never from the model.
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Technical reference
Specifications and terminal map.
Check the model, ratings and connection points against your own unit before choosing installation hardware.
Catalog specification
Legacy 25V-PV DCC30S: 30A dual-input charger for a 12V house bank, with 400W solar input. Combined charging is limited to 15A solar plus 15A alternator; newer DCC30S generations differ.
- Compatible systems
- 12 V
- Rated output
- 30 A
- Planning charge current
- 28 A
- PV open-circuit limit
- 25 V
Terminal map
ALT+ and START+ are aliases of one vehicle-input stud. BATT+ represents OUT+. Negative power paths share one NEG− stud. PV, IGN and sensing are outside this example; the newer DCC30S generation needs its own manual.
ALT +
positive · input
START +
positive · input
PV +
positive · input
PV −
negative · input
BATT +
positive · output
BATT −
negative · output
Sources and sizing method
Equipment specifications. Model details, ratings and terminal roles come from the catalog. Check your unit’s label and current manufacturer documentation for its exact revision.
Example sizing. Sized against ABYC E-11. Boats built to UK or EU rules answer to ISO 13297 — check these figures against it before you build. Results use the example current and run length shown above. Set your actual equipment, lengths and installation conditions in Crimp before choosing hardware.
Read how the sizing worksNext step
Plan your installation with DCC30S.
Open this example as a new project, or add this component to your existing diagram. Use your equipment and cable lengths to review the sizing.
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