8.2 Air Compressor¶
ARB Twin Compressor system with air tank and automatic pressure management for locker operation and tire inflation.
Model: ARB CKBLTA12 Brushless Twin Motor Onboard 12V Air Compressor
Status: Purchased
Product Page: ARB CKBLTA12
Installation Guide: ARB CKBLTA12 Installation PDF
Maximum Amperage Draw: 90A total (45A per motor × 2 motors)1
Fuse Configuration: Dual 60A MIDI fuses via SafetyHub 150 (one per motor)1
Location: Under passenger seat
Product Image:
Specifications¶
| Spec | Value |
|---|---|
| Motor Type | Brushless, twin motor |
| Voltage | 12V |
| Max Amperage | 90A total (45A per motor) |
| Duty Cycle | 100% |
| Maximum Pressure | 150 PSI |
| Air Flow @ 0 PSI | 9.18 CFM |
| Air Flow @ 29 PSI | 6.20 CFM |
| Cooling | Active cooling with built-in fans |
| Smart Start | Staggered motor power-on |
| Electronic Control | Speed control for temp/pressure |
| IP Rating | IP67 water resistant |
| Dimensions (L×W×H) | 14.49" × 13.31" × 6.69" |
| Weight | 15.8 lb (complete), 13.2 lb (bare) |
| Warranty | 3 years |
Control System¶
SwitchPros OUTPUT-11 (Button 11) provides a switched 12V control signal; the compressor's internal relay handles the high-current motor switching, so only a light 14 AWG control wire is needed alongside the 6 AWG motor power/ground (see Wiring table below).
Wiring¶
| Circuit | Source | Destination | Wire | Protection | Notes |
|---|---|---|---|---|---|
| Motor 1 Power | SafetyHub MIDI-1 (60A) | Compressor motor 1 positive | 6 AWG | 60A MIDI | Via SafetyHub 150A CB |
| Motor 2 Power | SafetyHub MIDI-2 (60A) | Compressor motor 2 positive | 6 AWG | 60A MIDI | Via SafetyHub 150A CB |
| Ground | Compressor negative terminal | AUX battery negative | 6 AWG | None | Direct for 90A return current |
| Control | SwitchPros OUTPUT-11 | Compressor control terminal | 14 AWG | 15A | Auto or manual activation |
Air Tank¶
ARB 1-Gallon Air Tank¶
Model: ARB 171507 (Aluminum, 1-gallon, 4-port)
Status: To purchase (targeting 1-gallon capacity)
Product Page: ARB 171507 Aluminum 1-Gallon Air Tank
Product Image:
| Spec | Value |
|---|---|
| Capacity | 1 gallon (4 liters) |
| Working Pressure | 150 PSI maximum |
| Material | Forged aluminum end caps + extruded aluminum body (~50% lighter than steel) |
| Mounting | Under passenger seat (horizontal or vertical) |
| Ports | 4 × 1/4" NPT (daisy-chain compatible) |
Pressure Switch¶
ARB Pressure Switch¶
Model: ARB 180901
Status: Purchased
Product Page: ARB Pressure Switch
Product Image:
| Spec | Value |
|---|---|
| Cut-In Pressure | 135 PSI (compressor starts) |
| Cut-Out Pressure | 150 PSI (compressor stops) |
| Mounting | On air manifold |
| Electrical | Low-current switch (<1A) |
Air Manifold¶
Configuration: 4-6 port brass manifold
Status: Purchased
Location: Under passenger seat (with compressor and tank)
Port Assignments:
- Input: Compressor output → manifold input
- Output 1: Manifold → Front locker solenoid (1/4" air line)
- Output 2: Manifold → Rear locker solenoid (1/4" air line)
- Output 3: Manifold → Rear Air Chuck Plate (1/4" air line)
- Output 4: Manifold → Pressure gauge (0-200 PSI, panel-mounted)
- Output 5: Manifold → Pressure switch (ARB 180901)
Automatic Pressure Control¶
SwitchPros Integration¶
Button 11 OR TRIGGER-3 → OUTPUT-11 (compressor). See SwitchPros TRIGGER-3 section for full programming logic.
Operational Modes:
| Mode | Control Method | Use Case |
|---|---|---|
| Automatic | Pressure switch via TRIGGER-3 | Normal operation - system maintains pressure automatically |
| Manual Override | Button 11 (latching mode) | Tire inflation - keep compressor running continuously |
| Off | Button 11 off + tank > 135 PSI | Compressor idle, tank maintains pressure for locker use |
Pressure Switch Wiring¶
| Circuit | Source | Destination | Wire | Protection |
|---|---|---|---|---|
| Pressure Switch Trigger | Pressure switch signal terminal | SwitchPros TRIGGER-3 (Pin 17) | 18 AWG | None (low current) |
Outstanding Items¶
High (1)
- ARB RD140 fitment with Revolution F10.25-513L in the Sterling 10.5 housing (#300) — The rear runs a 10.25" ring gear (Revolution F10.25-513L) in the 10.5 housing with the ARB RD140 carrier (Ford 10.25/10.5, 35 spline, all ratios). Confirm with ARB or Revolution that the RD140 flange and ring gear bolt pattern match the F10.25 gear in this housing before ordering, and confirm the pinion depth starting point (owner note: add roughly 0.120" to the pinion depth stack).
📋 Medium (3)
- Air locker air line service loop length at full droop (front and rear) (#303) — Measure the ARB air line service loop needed at each axle at full droop on the ORI struts (14" front, 16" rear travel), not at ride height. Sets the air line kit segment lengths from the manifold under the passenger seat (baseline estimates ~12 ft front, ~6 ft rear).
- Front Air Locker Solenoid Routing (#81) — Path for 18 AWG (~12 ft) from SwitchPros OUTPUT-17 (passenger rear wheel well) to front axle solenoid - cross-cab + forward
- Winch Trigger Control Routing (#80) — Path for 14 AWG control wire (~13 ft) from SafetyHub ATC-1 (passenger rear wheel well) to winch contactor (front bumper)
Build Tasks¶
- Verify ARB CKBLTA12 wiring harness connector pinout for motor 1, motor 2, and control terminals
- Confirm under-seat mounting bracket/location for compressor and 1-gallon tank
- Purchase ARB 171507 1-gallon aluminum air tank
- Order 0-200 PSI pressure gauge (panel-mount or in-line)
Related Documentation¶
- Air Lockers - ARB RD166 front / RD140 rear lockers
- Rear Air Chuck - External air access plate
- SafetyHub - Compressor power distribution
- SwitchPros - Compressor control (OUTPUT-11, TRIGGER-3)
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ARB publishes Max Amps 90 (total) for the CKBLTA12 brushless twin — matches our doc. The 45A per motor is the 90÷2 split (ARB does not publish a per-motor figure), and the 60A MIDI fuse per motor is this build's protection choice (not an ARB-specified value), sized above the ~45A per-motor draw. Source: ARB CKBLTA12 product page (checked 2026-05-30). NB: this is the brushless CKBLTA12 — do not apply specs from the older brushed CKMTA12 (28A/50A, 40A fuse), which is a different unit. ↩↩