800FM-SM44

1. Overview

The Allen-Bradley 800FM-SM44 is a 22mm panel-mount selector switch from Rockwell Automation's Bulletin 800F product family. The "FM" prefix denotes the metal (die-cast zinc alloy with chromate plating) variant of the 800F line, as opposed to the 800FP plastic version. The "SM" ordering code identifies it as a Selector switch with Maintained (non-spring-return, latching) operation using a standard black metal knob. The trailing digits "44" in the 800FM naming convention decode to: the first "4" indicating 4 positions (consistent with the 800FM-SM42 catalog pattern where SM42 = 4-position 2-contact), and the second "4" indicating 4 contact block positions or a 4-contact configuration — making the SM44 a 4-position, 4-contact maintained selector switch operator.

Important note on catalog classification: The existing Button Index entry categorizes this part as a "22mm E-Stop Push-Pull 40mm 1NC+1NO mushroom-push-pull" device, which does not match the actual 800FM SM-family ordering code structure. The SM operator family consists exclusively of selector switches, while mushroom push-pull emergency stops in the 800FM line use MP (push-pull) or MT/MK/MR (twist/key/ring release) codes. This appears to be a catalog data entry error.

2. User Sentiment

No direct user reviews or forum discussions specific to the 800FM-SM44 were found online, which is consistent with its status as a legacy or low-volume catalog SKU. Industrial users of the broader 800FM selector switch family (SM22, SM32, SM42) generally praise the die-cast metal construction as significantly more durable than the 800FP plastic equivalents for harsh environments — oil, coolant, and vibration being common concerns in machine tool applications. The 10A contact rating and IP66 sealing are frequently cited positives. No widespread complaints or field failure patterns were found for the 800FM SM-series.

3. Real-World Applications

The 800FM selector switch series is widely used in industrial machine control panels for mode selection (e.g., automatic/manual/jog/setup), safety interlocking, and process step selection in manufacturing environments. The metal-body 800FM variants are preferred in machine tool, stamping, and metal fabrication settings where plastic operators are prone to damage. The 4-position configuration (SM42/SM44) suits multi-mode machines requiring discrete position interlocking. Compatible with Allen-Bradley 800F contact blocks for integration into PLC and relay-logic control circuits.

4. Technical Specifications

• Type: 22mm non-illuminated selector switch operator (operator head only, no contact blocks included)
• Body: Die-cast zinc alloy with chromate plating (800FM = metal series)
• Actuator: Standard black metal knob (short thumb-grip design)
• Action: Maintained (latching/positive-detent, no spring return)
• Positions: 4 (based on SM4x family pattern; SM22=2-pos, SM32=3-pos, SM42=4-pos)
• Contact compatibility: N.O., N.C.E.B., or N.C.L.B. 800F contact blocks; N.C. and N.O.E.M. blocks are NOT compatible with 4-position selectors per Rockwell documentation
• Hole diameter: 22.5 mm
• Enclosure rating: IP66, NEMA Type 4/13
• Operating temperature: -25°C minimum
• Storage temperature: -40°C minimum
• Humidity: ≤95% RH (25–60°C range)
• Mechanical life: 1,000,000 cycles minimum (SM-series selector switches)
• Operating torque: Typical 0.25 N·m (2.2 lb·in) with one contact block
• Vibration/Shock: 10g / 100g
• Certifications: UL, CSA, CE (per 800FM-SM32 reference; CCC for China market)

5. Ordering & Compatibility

The 800FM-SM44 is a head-only operator and requires separate 800F series contact blocks (e.g., 800F-X01 for 1 N.C., 800F-X10 for 1 N.O., 800F-X11 for 1 N.C. + 1 N.O.) mounted to the back. Spring-clamp variants use 800F-Q series contact blocks. The metal SM-series selector switches are priced in the $40–$80 USD range at major distributors (based on SM32/SM42 comparables); no direct pricing was found for SM44. Related SKUs in the maintained metal selector family include 800FM-SM22 (2-position), 800FM-SM32 (3-position), and 800FM-SM42 (4-position, 2-contact); the SM44 likely represents the 4-position, 4-contact variant. The 800FP-SM42 is the plastic-body equivalent for less demanding environments.

6. Known Issues

No specific field issues or product advisories were found for the 800FM-SM44. For the broader 800FM SM selector switch series, it is important to note that 4-position variants restrict compatible contact block types — N.C. (standard) and N.O.E.M. (early-make) contact blocks cannot be used, which can trip up engineers migrating from 2- or 3-position designs. As an operator-only head, proper torque during panel installation and correct contact block latching are the most common assembly concerns cited for this product family. No recalls or safety notices found.