Description
Blue Sea Systems ML-ACR Automatic Charging Relay – 24V DC 500A
Model: 7621-BSS
- Automatically manages the charging of two large battery banks
- Allows paralleling of battery banks for emergency starting
- 500 Ampere continuous rating to support high-output alternators
- Magnetic Latch (ML)—ACR draws very low current (<40mA to monitor terminal voltage) in the "ON" or "OFF" states, and draws moderate current for very short time when changing state
- Dual sensing—senses charge on both battery banks
- Start Isolation (SI)—can be configured for temporary isolation of House loads from Engine circuit during engine cranking to protect sensitive electronics
- Engine Isolation (EI)—can be configured for isolation of two engines while both are running to protect engine electronics and maximize alternator output
- Senses charging on two battery banks
500 Amp magnetic latching (bi-stable) relay automatically combines batteries during charging and isolates batteries when discharging and when starting engine
Specifications
| Control Circuit Connection | Tinned Wire |
| Nominal Voltage | 24V DC |
| Manual Control | No |
| Engine Isolation | Yes |
| Mounting | 10 |
| Start Assist | Yes |
| Start Isolation | Yes |
| Amperage Operating Current | 13mA |
| Amperage Operating Current when changing state | <7.0A |
| Terminal Stud Torque | 140 in-lb (15.82 Nm) |
| Continuous Rating | 500A |
| Intermittent Rating | 700A (5 min) |
| Cranking Rating 30 sec | 1450A DC |
| Minimum Operating Temperature | -10° C |
| Maximum Operating Temperature | 60° C |
| Cable Size to Meet Ratings | 4/0 AWG x 2 |
| Live Current Switching | 300A @ 12V DC |
| Stud Material | Tinned Copper |
| Switching Cycles | 100000 |
| Terminal Ring Diameter Clearance | Terminal Ring Diameter Clearance |
| Terminal Stud Length | 1.50in (38.1 mm) |
| Terminal Stud Size | 3/8″ – 16 (M10) |
| Wire Size | 20 AWG |
What’s in the Box:
- ML-ACR Automatic Charging Relay 24v
- SPDT Remote Control Contura Switch – ON-OFF-ON



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