Installation & User Manual
Ed 19UK | June 2013 |
Before installing intrinsically safe units within an approved installation, it is essential to ensure that there are no deviations from the conditions of the order or the requirements of the approved block schematic diagram and the following related instructions:
1.No circuits other than those shown on the drawing are permitted. There must be no interconnection to any other circuits.
2.The intrinsically safe cabling must not be connected to
3.Adequate precautions must be taken to prevent danger arising from the charging of the intrinsically safe circuit by the contact leakage or inductance from any other circuit. To prevent static electricity do not rub cables or amplifier housing with a dry piece of cloth.
4.The intrinsically safe circuit must be adequately insulated from earth in the hazardous area and the insulation of all cabling must be at least 500 V r.m.s.
5.The safety barrier (zener barrier) must be placed in a safe area and be mounted within a protective enclosure with a protection degree, at least equal to IP 20.
6.The cable between the safety barrier and the amplifier should be provided with a cable shield which is connected to earth at the zener barrier. The impedance between the safety barrier earth rail and a secure bond to the hull must not exceed 1 ohm.
7.Safe area apparatus must not be supplied from, nor contain, a source of potential with respect to earth under normal or abnormal conditions exceeding 250V r.m.s. or 250 V DC.
8.The inductance/resistance ratio, total inductance and total capacitance, of the cable and the amplifier must not exceed the values stated by the manufacturer of the approved safety barriers.
9.Prevent impacts on the sensor housing to avoid sparks. Do not mount or dismount the sensor when there is a hazardous condition in the tank. Be sure the tank is vented and gas free.
10.Be sure that the amplifier box is dry and clean before the lid is mounted. The four screws in the lid should be tightened fully.
11.Be sure to order and use sensor cable with the right temperature specification. Check that the ambient temperature for the entire cable run do not exceed the max limit for the cable.
12.MAS2600 contain no repairable parts. Repairing or fixing the circuit or replacing components may impact the intrinsic safety.
13.The sensor cable shall remain in one piece from sensor to amplifier box.
Reference is made to manufacturer instructions of zener barriers and to the rules in force at the time in question concerning intrinsically safe area installation.
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