Ordering Information Model 5550 Mechanical Vibration Switch Hazardous Area Rating 4 ATEX/IECEx Flameproof Ex d IIB+H2 T6 GbEx tb IIIC T85°C Db Ta -40°C to +70°C IP66 silver contacts(1) Relay Contacts 2 DPDT, Silver, 15A(1)(2) Reset / Startup Delay Coil Holding Strength(3) 3 10g Reset / Startup Delay Coil Voltage 3 24 Vdc(4) Wiring Entry / Mounting Hole Pattern(5) 1 ¾” NPT / Metrix 5173 or 5175 Environmental Rating 0 NEMA 4 / IP66(6) Options A=0 through A=4 are only compatible with B=1 or B=2. Options A=5 through A=9 are only compatible with B=3 or B=4. INMETRO approvals (A=11) available with silver relay contacts only (B=1 or B=2)When D=0 (no reset /startup delay coil), the C option is ignored regardless of which value is selected. All switches ship with a full-scale range of approximately 16gs. When options C=2 and D=3 are simultaneously specified (2g, 24Vdc reset coil), the switch sensitive axis (see Figure 1 for 5550 and Figure 2 for 5550G) MUST be oriented vertically with the cover facing up. This coil lacks sufficient holding strength to support the trip plate when the switch is mounted horizontally or upside down. The switch may be mounted at any orientation for all other options. Consult Figure 1 for mounting plate dimensions corresponding to E options.If left blank, option 0 is provided.