Cutler-HammerS801T30N3SReduced-Voltage Solid-State Soft Starter – 304 A, 3-Phase, 200-600 V AC, 150 HP at 480 V, Internal Bypass, Selectable Class 5/10/20/30 Overload, 24 V DC Control

Product Description

Decoding the designation

S801T30N3S reads as follows

S801 – Eaton / Cutler-Hammer S801 open (non-combination) reduced-voltage solid-state soft starter, Intelligent Technologies (IT.) generationT – size T frame, the large chassis in the range (N and R are the smaller frames)30 – the amp code for this frame: 304 A maximum motor FLA. Within the T frame, 13 = 130 A, 18 = 180 A, 24 = 240 A, 30 = 304 A. On the smaller N frame the code is the literal amp figure, e.g. N37 = 37 A, N66 = 66 AN3S – control-power and construction suffix. On this unit the nameplate confirms what it resolves to: 24 V DC control voltage (Uc – 24 VDC), three-pole / three-phase switching, and standard open-chassis construction. Eaton publishes this group only in the S801 selection tables, so we are reporting the nameplate rather than asserting a letter-by-letter keyEaton’s current catalogue equivalent is written S801+T30N3S. The + denotes the later generation of the same family; Eaton’s own SKU page maps this catalogue number straight through. Nameplate style number on this unit is 92EA10020A0001A.

Published ratings and mounting data

Maximum motor FLA: 304 ASupply: 200-600 V AC, three-phase, 47-63 HzNominal load voltages: 208 / 240 / 380 / 480 / 575 V ACHP by voltage: 60 HP at 200/208 V · 75 HP at 230/240 V · 150 HP at 460/480 V · 200 HP at 575/600 V (Eaton also quotes 90 kW at 230 V, 160 kW at 380-400 V, 185 kW at 440 V)Rated insulation voltage Ui: 660 V ACControl voltage: 24 V DCPoles: 3, in-line connection, six SCRs (terminals 1/L1, 3/L2, 5/L3 to 2/T1, 4/T2, 6/T3)Internal run bypass contactor: yes, 10 million operation mechanical lifeOverload: 450 % for 30 seconds; trip class selectable 5 / 10 / 20 / 30; FLA setting range 30-100 % of ratingRelay contact rating: 3 A at 24 V DC / 120 V AC (240 V AC and 120 V DC maxima)Ambient: -30 to +50 °CEnclosure: open chassis (no NEMA rating – mount in a suitable enclosure)Dimensions and weight: 19 x 14.5 x 12.5 in, 45 lb (Eaton); 40 lb net per distributor dataApprovals: c-UL-us, CSA, CE

The FLA dial is the part people get wrong:
This is not a fixed-current starter. The front label carries a four-position FLA DIAL ADJUSTMENT table – A = 95 A, B = 164 A, C = 233 A, D = 304 A – and the electronic overload then trims within 30-100 % of the selected step. So one T30 unit legitimately protects motors from roughly 29 A up to 304 A. Set the dial to the step at or just above your motor’s nameplate FLA and then set the fine FLA adjustment to the actual value; leaving it at D on a 100 A motor gives you a starter that will happily let the motor cook. This adjustability is also the reason a used T30 is worth buying for a smaller motor – you are not oversized out of protection.

Why a soft starter instead of a contactor or a VFD:
Against an across-the-line contactor: a direct-on-line start draws six to eight times FLA and delivers a torque step that snaps couplings, shreds belts, water-hammers pumps and trips the utility’s demand meter. The S801 ramps voltage so inrush and starting torque are controlled. On a 150 HP 480 V motor that is the difference between a service that holds and one that does not.

Against a VFD: a soft starter only controls the start and stop. Once up to speed the bypass contactor closes and the SCRs are out of circuit, so there are no running losses, no harmonics, no motor-cable dV/dt problem and no need for an inverter-duty motor. If you do not need speed control, a soft starter is cheaper to buy, cheaper to run and far less trouble electrically. If you do need speed control, no soft starter substitutes for a drive.

Starting, stopping and protection features

Selectable kick start (torque pulse to break away a sticky load), voltage-ramp start and current-limit start, plus soft stop for loads that must not be dropped abruptly – a conveyor with an unsecured product, or a pump where a hard stop causes column separation. Adjustments visible on the front label: torque 0-85 % initial, ramp time T1/T2 0.5-180 s, kick time tk 0-2 s, soft stop 0-60 s, FLA dial A-D, overload trip class 5/10/20/30.

Protection, individually switchable to ON or DISABLE on the front DIP bank: over temperature, overload, jam, stall, phase loss, phase reversal, plus manual/auto reset selection. Also included: shorted-SCR detection, phase imbalance, under- and overvoltage, undercurrent and internal diagnostics. Hardwired 24 V DC inputs for start, stop, jog, overload disable and fault reset; a normally-open contact for bypass indication and a form-C fault relay (terminals 13/14 and 95/96/98); a status LED, a local reset pushbutton and a TTL port.

Installation and setup notes

Open-chassis construction – there is no enclosure rating, so this must go into an appropriate NEMA enclosure with the ventilation Eaton specifies for the T frame. Line and load lug kits mount on either side. Branch-circuit protection, disconnect means and short-circuit coordination are all external and must be selected per the S801 manual and the NEC – a soft starter is not a short-circuit protective device. Control power is 24 V DC only on this unit; if your panel has 120 V AC control you need a supply, or a different control-voltage variant.

Brand and obsolescence trail

Cutler-Hammer is Eaton. Eaton acquired Cutler-Hammer and progressively retired the brand name on new product, so parts branded Cutler-Hammer, badged Intelligent Technologies or IT., are earlier production of what Eaton now sells. Continuity is direct: S801T30N3S → S801+T30N3S, still an Eaton catalogue number with published specifications, documentation (S801+ user manual MN03900002E) and technical support. The wider family also includes the S811+, Eaton’s more feature-rich soft starter, and the legacy S611 and S801N/S801R frames. Search this part as S801T30N3S, S801-T30N3S, S801+T30N3S or S801 T30N3S – all four forms are in circulation.

Condition and what is included

Used. Plastics damaged in shipping – see the photographs and judge for yourself; the visible damage is to the moulded covers rather than to the power terminals or SCR block, but assess it against your own inspection standard. The unit is complete as pictured with its control terminal block, front label, DIP protection selectors and adjustment dials. No enclosure, no lug kit, no communication module, no manual, no mounting hardware. Not functionally tested. Made in U.S.A. per the nameplate.

Communications

The S801 has no communication protocol built in. Network connectivity – Modbus, DeviceNet, PROFIBUS, Ethernet – is added through Eaton’s S811+/S801+ communication modules, which are separate items and are not included here. Do not assume this unit will talk to a PLC out of the box; it will accept hardwired 24 V DC commands and provide relay outputs, and that is all.