Anderson SB series: SB50, SB175, SB350
The Anderson SB series is the standard battery connector on electric forklifts across North America. It is a genderless design, which means both halves of the connection are identical — there is no male plug and female plug to keep straight, just two matching housings that push together. The contacts inside are rated by current, and the series number tells you that rating.
- SB50 — 50 amps, light duty. Found on electric pallet jacks, walkies, and small stackers. Small housing, light cables, and enough capacity for low-current 24V applications.
- SB175 — 175 amps, mid-size. The most common connector in indoor distribution. Fits mid-size counterbalance trucks, order pickers, and reach trucks, usually at 36V.
- SB350 — 350 amps, heavy duty. For heavy-duty trucks with high current draw, usually at 48V and above. Larger housing, heavier cable, and built to handle sustained high current without overheating.
SB housings are color-coded by voltage, which is a safety feature as much as a convenience: grey is commonly used for 36V, blue for 48V, and red for 24V, though conventions can vary by fleet and manufacturer. The color is a helpful hint, not a guarantee — always confirm voltage from the data plate or battery label rather than trusting the plug color alone. A connector from one voltage will physically fit a connector of another voltage in the same series, so color is the only thing stopping a 36V battery from being plugged into a 48V truck. Keep the colors consistent in your fleet and the system works.
Euro DIN connectors
Trucks built in Europe — and some trucks built for the European market and imported — use Euro DIN connectors instead of the Anderson SB series. These are usually rated at 80, 160, or 320 amps, and they look different: a rectangular housing with keyed pins that only fit together one way.
The keying is the point. Unlike the SB series, where color is the main guard against a voltage mismatch, DIN connectors use physical key pins arranged in different positions for different voltages, so a 48V DIN plug physically cannot mate with a 24V DIN socket. That makes them more foolproof, but it also means there are more variants to keep straight, and a replacement has to match the key pattern exactly, not just the current rating.
If your fleet includes European trucks, stock the DIN variants you actually use and do not assume an SB connector can be swapped in without changing the truck-side and charger-side plugs to match. The whole chain — battery, truck, charger — has to agree on one connector type.
SMH and SY series, briefly
You may also run into SMH and SY series connectors, which are Anderson's variants for specific applications. SMH connectors are used on some charger connections and smaller equipment, and the SY series covers certain single-pole and multi-pole configurations. They are less common on the battery side of a forklift, but they show up often enough that a technician will recognize them.
The practical rule is the same as for the SB and DIN series: match the connector type, the current rating, and the voltage, and do not mix series. If a plug on your truck does not look like an SB or a DIN, take a photo and send it to your dealer before ordering anything. Guessing at connector types from a catalog picture is how the wrong part arrives twice.
How to identify your connector
Identifying a connector takes about thirty seconds once you know what to look at. Check three things, in this order.
- Housing size. Compare it to the SB series: a small housing is likely an SB50, a medium one an SB175, and a large one an SB350. A rectangular keyed housing is likely DIN.
- Housing color. On SB connectors, the color hints at the voltage — grey, blue, and red are the common ones. Record the color alongside the size.
- Markings on the housing. The series and current rating are usually molded into the plastic, along with the manufacturer's mark. Worn housings can be hard to read; a phone photo in good light usually captures enough.
If the housing is melted, cracked, or too worn to read, do not guess — send your dealer a photo of the plug on the truck side and a photo of the plug on the charger side. Those two photos are enough to identify the connector and quote a replacement.
Matching connector to charger and truck
A battery has one connector, but it has to mate with two things: the truck and the charger. All three ends have to be the same connector type, the same series, and the same color code for the voltage. A battery with an SB175 grey plug needs a truck with an SB175 grey socket and a charger with an SB175 grey plug.
When you order a replacement battery, confirm the connector with the dealer rather than assuming it will match the old battery. Most replacement batteries ship with the connector that matches the original spec, but a previous owner may have changed the truck-side plug, and fleets sometimes standardize on one connector across trucks that originally shipped with different ones. The ordering conversation should always include the words: series, color, and current rating. If you are also buying a new charger, our charger overview covers how to match charger and battery together.
Damaged connectors and replacement
Connectors fail gradually and then all at once. The warning signs are heat, discoloration, a loose fit, or a plug that needs to be wiggled to make contact. A connector that runs hot is a connector with high resistance — loose or corroded contacts generate heat, heat accelerates corrosion, and corrosion raises resistance further. Left alone, the housing melts, the truck stops, and the repair grows from a plug replacement into a cable and contact replacement.
Replace a damaged connector promptly, and replace it with the same type and rating — never a smaller one. An SB175 will physically fit where an SB350 belongs, but it will overheat under the higher current and fail again, faster. Connector replacement is a technician job: the contacts are crimped onto heavy cable with proper tooling, and a poor crimp is just a new failure waiting to happen. While the technician is there, have them check the truck-side and charger-side plugs too — if one end is worn, the mating end usually is as well. For the bigger picture on keeping batteries and their hardware healthy, the technical specs guide covers the full battery system, connectors included.