Why two 10-port stations can differ by RMB 2,800
Market prices for 10-port units run from RMB 1,200 to 4,000. Take one apart and the difference sits in four places — all four safety-critical:
- Leakage protection. Cheap units share one RCD across all ten ports: a single faulty port blacks out the station, and the trip threshold runs large. We fit an independent RCD per port, 30mA, tripping under 0.1 seconds.
- Overload self-recovery. Chargers draw 120–300W, but aged batteries or knock-off chargers can pull 500W+. Without protection, sustained overheating follows — a leading cause of charging fires. Ours disconnects and auto-recovers, no manual reset.
- Full-charge auto-stop. Current-drop detection cuts the charge and avoids endless float-charging that swells batteries; an 8-hour forced cutoff backs it up.
- Outage memory. After a blackout the station restores billing state — no double charges, no disputes. Underrated until the first summer thunderstorm.
10 ports or 20? Size by users, not by households
The working rule: one charging port per 30–50 active e-bikes — take the upper bound in new, e-heavy communities, the lower in old ones. A 500-household community typically counts 200–350 e-bikes: 8–12 ports (one or two 10-port units) usually suffice, plus 30% headroom if demand concentrates 18:00–22:00. Placement beats count: near building entrances without blocking passages, lit and covered by CCTV, on hardened non-ponding ground, at least one metre from gas pipework.
Payment: QR, card or coin
QR payment (WeChat / Alipay) dominates — about 87% of sessions in our operating data — but card-using elderly residents still account for 15–25% in some communities, so we run QR and card together, with coin modules as an option. One compliance note: payment flows must run through a licensed payment channel; never let money pool in an unlicensed account.
Yantai-specific installation details
Winters reach −10°C: outdoor units need low-temperature-rated components and anti-freeze cable. Coastal districts (Zhifu, Laishan seafront) suffer salt spray: prefer 304 stainless or coated enclosures — plain cold-rolled steel rusts through in about two years. All cabling runs in conduit with tray earthing resistance at or below 4 ohms; in underground garages use flame-retardant (ZR) cable and fire-seal every wall penetration.
Price and payback
10-port unit with standard installation (cabling within 30 m, RCD box, signage): RMB 12,000–22,000 in the Yantai area; 20 ports about RMB 18,000–32,000. New shelters quoted separately on the shelter page. At 1.5 uses/port/day and RMB 1 per session, a 10-port station grosses about RMB 450/month; after electricity (about RMB 0.6/kWh, 0.5 kWh per session) and platform fees, net lands around RMB 250–300/month — payback in 3–5 years, halved where sheltered, managed stations price at RMB 2. Model your own case in the payback calculator.
The safety configuration checklist
- Independent RCD per port — one faulty port never blacks out the others.
- Full-charge auto-stop — no overnight float-charging, no heat build-up.
- Overload disconnection with self-recovery — no morning-after reset rounds.
- Outage memory — billing survives blackouts.
- Flame-retardant enclosure and conduited cabling — what the fire inspection actually checks.
Quotes rarely itemise these; ask for each by name. More answers in the FAQ; for capacity and sharing questions, see the model comparison.