Pressure switch and Thermostat CAS
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Data sheet Pressure switch and Thermostat CAS The CAS Series consists of a series of pressure controlled switches and temperature controlled switches. In this series, special attention has been given to meeting demands for a high level of enclosure, robust and compact construction and resistance to shock and vibration. The series is suitable for use in alarm and regulation systems in factories, diesel plants, compressors, power stations and on board ships. • A high level of enclosure • Fixed differential • Robust and compact construction • Resistance to shock and vibration • Available with all major marine approvals CE-marked in accordance with LVD 2006/95/EC Ship approvals American Bureau of Shipping, ABS (excl. CAS 139) Lloyds Register of Shipping, LR (excl. CAS 1080) Germanischer Lloyd, GL Bureau Veritas, BV Det Norske Veritas, DNV Registro Italiano Navale, RINA Maritime Register of Shipping, RMRS Nippon Kaiji Kyokai, NKK

Data sheet | Pressure switch and Thermostat, type CAS Overview Standard pressure switches

Data sheet | Pressure switch and Thermostat, type CAS Enclosure IP67 acc. to EN 60529. The pressure control housing is enamelled pressure die cast aluminium (GD-AISi 12). The cover is fastened by four screws which are anchored to prevent loss. The enclosure can be sealed with fuse wire. Identification The type designation and code no. of the unit is stamped in the side of the housing.

Preferred version Range setting The pressure range within which the unit will give a signal (contact changeover). Differential The difference between make pressure and break pressure (see also page 6). Permissible burst pressure The highest permanent or recurring pressure the unit can be loaded with. Max. test pressure The highest pressure the unit may be subjected to when, for example, testing the system for leakage. Therefore, this presure must not occur as a recurring system pressure. Min. burst pressure The pressure which the pressure-sensitive element will withstand without leaking.

Data sheet | Pressure switch and Thermostat, type CAS Function a. CAS 155 Contacts 1-4 make and contacts 1-2 break when the differential pressure rises above the set range value. The contacts changeover to their initial position when the differential pressure again falls to the range value minus the differential (see fig. 1). I. larm for rising pressure A given at the set range value II. larm for falling pressure A given at the set range value minus the differential b. All other CAS pressure switches Contacts 1-2 make and contacts 1-4 break when the pressure falls under the set range value....

1. Range spindle 2. Range scale 3. Locking screw Installation CAS pressure switches are fitted with a 3 mm steel mounting plate. The units should not be allowed to hang from the pressure connection. Pressure connection When fitting or removing pressure lines, the spanner flats on the pressure connection should be used to apply counter-torque. Steam plant To protect the pressure element from excessive heat, the insertion of a water-filled loop is recommended. The loop can, for example, be made of 10 mm copper tube as shown in fig. 3. Water systems Water in the pressure element is not...

Data sheet | Pressure switch and Thermostat, type CAS Dimensions [mm] and weights [kg] Net weight: CAS 133-139 approx. 1.0 kg CAS 143-147 approx. 1.3 kg CAS 155 approx. 1.5 kg

Data sheet | Pressure switch and Thermostat, type CAS Preferred version Enclosure IP67 acc. to EN 60529. The thermostat housing is enamelled pressure die cast aluminium (GD-AISI 12). The cover is fastened by four screws which are anchored to prevent loss. The enclosure can be sealed with fuse wire. Identification The type designation and code no. of the unit is stamped in the side of the housing.

Note: All sensor pockets are supplied without gland nut, gaskets and washes. Other Accessories

Data sheet | Pressure switch and Thermostat, type CAS Installation Location of unit: CAS thermostats are designed to withstand the shocks that occur, for example, in ships on compressors and in large machine installations. CAS thermostats are fitted with a base of 3 mm steel plate for fixing to bulkheads, etc. Resistance to media Material specifications for sensor pockets. Sensor pocket brass The tube is made of Ms 72 to DIN 17660, the threaded portion of So Ms 58 Pb to DIN 17661. Sensor pocket, stainless steel 18/8 Material designation 1.4305 to DIN 17440. Sensor position As far as...

Data sheet | Pressure switch and Thermostat, type CAS Installation Scale correction The deviation can be compensated for as (continued) The sensor on CAS thermostats contains an follows: adsorption charge. Therefore function is not Scale correction = Z x a affected whether the sensor is placed warmer or Z can be found from fig. 12, while "a" is the colder than the remaining part of the correction factor from the table below. thermostatic element (bellows and capillary (See example, page 14). tube). However, such a charge is to some extent sensitive to changes in the temperature of bellows...

Data sheet | Pressure switch and Thermostat, type CAS Electrical connection CAS thermostats are fitted with a Pg 13.5 screwed cable entry suitable for cables from 5 – 14 mm. Installation (continued)

Data sheet | Pressure switch and Thermostat, type CAS Function Differentials The mechanical differential is the differential determined by the design of the thermostat. The thermal differential (operating differential) is the differential the system operates on. The thermal differential is always greater than the mechanical differential and depends on three factors: 1) Medium flow velocity 2) Temperature change rate of the medium 3) Heat transmission to the sensor Thermostat function Contacts 1-4 make while contacts 1-2 break when the temperature rises above the scale setting. The contacts...

Data sheet | Pressure switch and Thermostat, type CAS Function (continued) CAS 1080 thermostats have fixed factory settings. The thermostats with factory setting at 80 °C of step 1 and step 2 is used for special application, where double warning – like cranck case fire – is requested. The contacts automatically reset when the temperature decreases in accordance with the differential. Differentials The mechanical differential is the differential determined by the design of the thermostat. The thermal differential (operating differential) is the differential the contact system operates on....