Two decisions fix an energy-storage connector: how much current the circuit will carry, and which stage configuration the mating interface needs. Voltage class usually settles itself, because the whole range is rated DC 600 V. Work through the current class first, then the stage configuration, and confirm the interface last.
Step 1 — Size the current class against the circuit, not the label
Use the highest current the circuit will actually carry: continuous current plus any peak or surge the load draws, and the discharge current the battery can deliver under fault conditions. The range covers 30 A to 350 A, and the classes are not evenly spaced, so pick the next class above the calculated figure rather than the nearest one.
Be aware that a connector rated at a current is rated for that current as a complete connection — the cable, the crimp and the mating half all have to carry it as well. A 350 A connector on a cable rated for less simply moves the limiting point.
Step 2 — Match the stage configuration to the mating interface
This range is supplied in single-, two- and three-stage versions, and the correct one is determined by the interface you are connecting to, not by preference. Some storage architectures use separate connection stages for different functions in the same housing; others use a single contact pair. Both single-stage and multi-stage interfaces exist in the field.
Because the stage configuration has to mate mechanically as well as electrically, treat this as a specification to confirm rather than a feature to select. Send us the interface drawing or the mating part you are working to, and we will confirm which of the single-, two- and three-stage models matches. Do not assume a two-stage connector will fit a single-stage interface.
Step 3 — Check the voltage class of the system as a whole
The whole range is rated DC 600 V, so within this product line the voltage class is not a variable. What still has to be checked is the system around it: a 600 V connector installed in a circuit whose maximum system voltage exceeds that is a misapplication regardless of the connector's own rating. State your maximum system voltage when you enquire.
The range at a glance
| Stage configuration |
Current classes |
Models |
| Single-stage |
30–45 A, 75 A, 120 A, 180 A |
PP30A-45A, PP75A, PP120A, PP180A, SBS-75X, FS-50A |
| Two-stage |
40 A, 50 A, 80 A, 120 A, 175 A, 350 A |
SY-40A, SY-50A, SY-80A, SY-120A, SY-175A, SY-350A |
| Three-stage |
50 A, 175 A |
SY-50A-3, SY-175A-3 |
All models are rated DC 600 V. Where a current class appears in more than one stage configuration — 50 A and 175 A both do — the stage configuration is the deciding difference, not the current rating.
What to verify before you order
- The maximum current the circuit will carry, including peak and fault conditions.
- The stage configuration of the interface you are mating with, confirmed against a drawing or a sample.
- The cable cross-section the connector must accept, and the termination method.
- Your maximum system voltage.
- The standard the installation must be certified to, and its current derating rules for your ambient temperature.
Common selection mistakes
- Sizing on nominal current. Storage circuits carry discharge peaks and fault currents well above the nominal figure.
- Assuming a stage configuration will mate. Single-, two- and three-stage interfaces are not interchangeable.
- Buying for the current and ignoring the cable. The connection is a system, and the weakest element sets the limit.
- Skipping the derating table. A connector's rating assumes a reference ambient temperature; a hot cabinet changes the acceptable class.
