Certificate history:
This certificate is issued as verification that a sample(s), representative of production, was assessed and tested and found to comply with the IEC Standard list below and that the manufacturer's quality system, relating to the Ex products covered by this certificate, was assessed and found to comply with the IECEx Quality system requirements. This certificate is granted subject to the conditions as set out in IECEx Scheme Rules, IECEx 02 and Operational Documents as amended.
This Unit verification certificate is issued as verification that the Apparatus identified on page 1, was assessed and tested and found to comply with the IEC Standard list below. This certificate is granted subject to the conditions as set out in IECEx Scheme Rules, IECEx 02 and Operational Documents as amended.
STANDARDS: The electrical apparatus and any acceptable variations to it specified in the schedule of this certificate and the identified documents, was found to comply with the following standards:
As this is a Unit Verification Certificate, no QAR is applicable as this certificate is specific to the items listed by serial number or other unique identification.
The Model 220 Pressure Switch is for measuring differential pressure and comprises a pressure assembly and cover housing a single or double reed switch assembly and either a circuit board with a terminal strip interface or a single or double relay assembly with terminal strip interface. The switches, or switches, and pressure indication are magnetically coupled to a moving magnet inside the pressure assembly.The cast body (pressure assembly) and cover are manufactured from aluminium with a maximum working pressure rating of up to 20.7MPa (3000psig). The body may optionally include a stainless steel insert to provide all stainless steel wetted parts. The cover is secured to the body with seven M5, stainless steel hexagon head captive screws. Internal and external earth facilities are provided. A ½” NPT cable entry hole is provided for the accommodation of a cable entry device, with or without the interposition of a flameproof thread adapter. The cable entry device, and thread adapter if fitted is to be suitable for the equipment, the cable and the conditions of use and shall be certified as Equipment (not a Component).Variation 0.1An alternative version with a maximum working pressure rating of up to 10.3MPa (1500psig). In this form the equipment is designated a Model 240 Pressure Switch.Variation 0.2The optional fitting of an external dial gauge assembly for the indication of differential pressure. Variation 0.3The optional replacement of the magnetic switches with an electronics unit having a 4-20mA proportional output. In this form the unit is designated a Transmitter Unit.Further description can be found in the Certificate Annex
