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Quick Verdict

A low-energy operator (ANSI/BHMA A156.19) opens a manual door on a knowing act, a push plate or touchless switch, and works as a normal closer the rest of the time. Pick the model by mounting side first: pull side takes a slide track arm (LCN 4631, Norton 5710, Falcon 8231), push side takes a double lever arm (LCN 4642, Norton 5730, Falcon 8242), and the Norton 5740 ships with both arms when the side is undecided. LCN 4640 handles 36 to 54 in. doors at 90 degrees powered; Norton 5700 needs a 29 in. minimum single door. Then add two actuators and latching hardware the operator can open: an electric latch retraction exit device or an electric strike. A door that stays latched defeats any operator.

Low energy or full energy: which standard applies?

Two ANSI/BHMA standards split the market. A156.19 covers power assist and low-energy power operated doors: the door opens on a knowing act (a push plate, a touchless switch, a fob) at reduced speed and force, and it still operates as a manual door. A156.10 covers full-energy power operated pedestrian doors: the door opens on presence detection at full speed, which brings sensor and guarding requirements a low-energy unit does not carry.

For the swing doors this article covers (accessible entrances, restrooms, corridor doors, clinic suites), low energy is the default. The LCN 4640 and 4630 units are certified to A156.19 and A117.1; the 4631 also carries UL 325/228. All the models below operate manually when the power is off: Norton states the 5700 runs as a mechanical surface closer during close cycles, when opened by hand, or with power off.

Low-energy operators do not replace a correctly sized closer on doors that do not need power. Closer sizing is covered in our closer adjustment and sizing guide, and the accessibility context, including the 5 lbf interior opening force under ADA 404.2.9, is in ADA compliance for commercial door hardware.

If the opening is an accessible swing door with a knowing-act actuator, order from the power operator category.

LCN 4600 series: 4631 pull side or 4642 push side?

LCN builds two families that searchers group as "4600".

LCN 4642 (4640 auto equalizer). Grade 1, surface mounted, electrohydraulic, top jamb push side mount with a double lever arm, for 36 to 54 in. doors, 90 degrees powered and 100 degrees manual swing. Spring size adjusts 2 to 5. Butt hinges should not exceed 5 in. wide. A 4-1/2 in. reveal allows 90 degrees powered and 100 degrees manual; an 8 in. reveal needs the long arm, where the standard rod and shoe are replaced by the 4640-79LR long rod and shoe. Top rail minimum is 1-3/4 in., and flush ceiling installs need 3-3/4 in. minimum. The LCN 4642-REG is the regular arm version; the 4642-LONG covers deep reveals.

LCN 4631 (4630 Benchmark). Grade 1, low energy, electromechanical, pull side mount with a standard slide track arm, for 36 to 48 in. doors, 90 degrees powered and 170 degrees manual. Spring size adjusts 1 to 4. Reveal should not exceed 1/8 in.; top rail minimum 1-1/8 in.; head frame minimum 2 in. Hold-open time adjusts up to about five minutes. The LCN 4631-STD runs about $5,982 at NLS.

Both families are non-handed and come in 689 aluminum, 690 statuary bronze, 691 light bronze, 693 black, 695 dark bronze and 696 brass, and both meet the Buy American Act per LCN, which matters on public work. Arm geometry and reveal limits are compared in door closer arm types and mounting options.

Norton 5700 series: 5710, 5730 or 5740?

Norton's 5700 units are built around a heavy-duty Norton 1601 closer, so spring force gives the feel of a manual closer, with adjustable spring power, backcheck, sweep and latch valves.

• Norton 5710, pull side: slide track arm, adjustable stop, 110 degree swing (trim permitting). Minimum door width 29 in. single, 30 in. per leaf on pairs. About $3,266 at NLS.
• Norton 5730, push side: standard duty double lever arm, frame reveals 2-5/8 to 6-3/4 in., 170 degree swing (trim permitting). An auxiliary door stop is required.
• Norton 5740, universal: the Norton 5740 kit includes operator, cover, and both push and pull arms. Order it when the mounting side is not final or for stocking one unit across several openings.

Every 5700 unit has an onboard 24 VDC (1.1 A) supply for accessories, an end-user on/off switch, adjustable hold open, obstruction detection, an open delay for locking hardware, and an overload shut-off that closes the door after 2 minutes of continuous activation signal.

Model	Mounting side	Arm	Key spec from the product sheet	Order page
LCN 4642-REG	Push, top jamb	Double lever, regular	36 to 54 in. door, 90 deg powered, 100 deg manual	4642-REG
LCN 4642-LONG	Push, top jamb	Double lever, long	8 in. reveal with 4640-79LR long rod and shoe	Power operator category
LCN 4631-STD	Pull	Slide track, standard	36 to 48 in. door, 90 deg powered, 170 deg manual	4631-STD
Norton 5710	Pull	Slide track	110 deg swing, 29 in. minimum single door	Power operator category
Norton 5730	Push	Double lever, regular	2-5/8 to 6-3/4 in. reveal, auxiliary stop required	Power operator category
Norton 5740	Push or pull	Both arms included	Same limits as 5710 and 5730	5740
Falcon 8242-REG AL	Push	Double lever, regular	26 in. header, 200 lb door, 12 VAC onboard supply	Power operator category
Falcon 8231-STD AL	Pull	Slide track, standard	Push 'n' Go, SmartLatch, pre-load strike assist	Power operator category

Pick the row by mounting side and reveal, then order from the power operator category.

Which actuators should you pair: push plates or touchless?

Every low-energy door needs a knowing-act actuator on each side, usually two per opening.

• Hardwired push plate: the BEA 10PBO241 is a 2-3/4 x 4-1/2 in. single gang, 16 gauge 304 stainless plate with "Push to Open" text and handicap logo, a single-pole 15 A switch (COM/NO/NC), and compatibility with BEA wireless transmitters on 900, 433 or 300 MHz.
• Touchless, wired: the RCI 910TC uses capacitive sensing with infrared, a detection zone up to 2 in., 12 to 24 VDC, a Form C SPDT relay at 24 VDC 100 mA, selectable unlock times of 1 to 63 seconds or toggle, and a secondary normally open mechanical switch if power is lost. It fits single-gang (2-15/16 x 4-11/16 in.) or mullion (1-3/4 x 4-1/2 in.) and runs about $109 at NLS.
• Touchless, wireless: the RCI 912 series is battery powered (four AA), infrared, 2.4 GHz with about 100 ft line of sight, detection adjustable from 1 to 12 in., and an SPDT receiver output rated 3 A at 30 VDC on a 12 to 30 VDC input. The 912-2WBT-R-HC kit includes two switches and the receiver.

The Norton onboard 24 VDC (1.1 A) supply and the Falcon onboard 12 VAC supply can power actuators and receivers without an external supply; check the actuator voltage against the operator before ordering. Order actuators in pairs from the power operator category.

Which latching hardware works with the operator?

An operator cannot pull a latched door. The latch has to be out of the strike before the arm moves, which means one of three setups.

Opening type	Latching hardware to pair	Why
Exit device door, steel or wood	Electric latch retraction exit device	Retracts the latch in the device; door swings free on the actuator signal
Narrow stile aluminum storefront	ELR narrow stile device or electric strike for the deadlatch	The strike releases the latch; ELR suits pairs and rod devices
Lever lock door (restroom, office)	Fail-secure or fail-safe electric strike	Strike keeper releases so the operator can swing the door
Door unlatched during open hours	Operator with no electrified latch, latch held retracted	Only when the schedule and code allow an unlatched door

Brand-by-brand ELR devices and retrofit kits are in our ELR exit device guide; storefront strikes are compared in Adams Rite 7100 vs 7400 electric strikes. Use the Norton open delay so the operator waits for the latch to release; the Falcon 8200 adds a pre-load strike assist that removes load on the strike lip with a one second delay. Fire-rated doors with operators must close and latch on alarm; the authority having jurisdiction (AHJ) reviews the wiring and sequence, and electrical work belongs to a qualified technician.

Order the operator and the ELR device or strike on the same PO so voltages and timing match.

Which replacement parts do LCN 4640 operators use?

Repairing a 4640 is usually cheaper than replacing the unit. Parts carried for the 4640 series:

• 4640-3454 motor/clutch assembly: the geared assembly with LCN's "no destruct" feature, about $1,610 at NLS.
• 4640-3180 I/O board assembly: high and low voltage PC boards on the mounting bracket.
• 4640-3179-2 hold open switch: black rocker switch field wired to the low voltage board.
• 4640-3077 standard arm: non-handed, in 689 or 695.
• 4640-334-2 plain end cap: with two end cap screws.

These parts are listed for the 4640 series; for 4630 Benchmark units, confirm the part with the order desk. Order 4640 parts from the power operator category.

Common mistakes

1. Ordering a push side operator for a pull side mount. Mounting side sets the model: 4642 and 5730 push, 4631 and 5710 pull.
2. Missing the reveal: 4640 needs the long arm with 4640-79LR above 4-1/2 in.; 5730 tops out at 6-3/4 in.
3. Leaving the door latched with a passage lever and no strike or ELR.
4. Skipping the auxiliary stop the Norton 5730 requires.
5. Ordering one actuator. The opening needs one on each side.
6. Treating a low-energy operator as an A156.10 full-energy door with presence sensors.
7. Buying a 4640 part for a 4630 unit without confirming fit.

FAQ

What is the difference between a low energy and a full energy door operator? Low-energy operators (A156.19) open on a knowing act at reduced speed and force and still work as manual doors. Full-energy operators (A156.10) open automatically on presence detection at full speed and need safety sensors.

What does the LCN 4642 auto operator include? A Grade 1 electrohydraulic push side operator with a double lever arm (regular or long), metal cover and wood and machine screws, for 36 to 54 in. doors. Actuators and latch release hardware are ordered separately.

Is the Norton 5710 push or pull side? Pull side, with a slide track arm and 110 degree swing. The push side model is the 5730, and the 5740 includes both arms.

What is a wave to open actuator? A touchless switch such as the RCI 910TC that triggers the operator on a hand gesture inside a 2 in. detection zone. It replaces a push plate with the same knowing-act function.

Next step

Choose the model by mounting side and reveal, then order from the power operator category: the LCN 4642-REG, the LCN 4631-STD or the Norton 5740, plus two actuators. Orders by 3 p.m. ET ship the same day; $450 and up ships ground free. Multi-door accessibility packages go to the quote desk; agencies use government PO intake.