CAN CSA C50089-99:2016 pdf download.Cast resin partitions for metal-enclosed gas-filled high-voltage switchgear and controlgear
3.1 Design pressure
Since in service most partitions have the same or small differential pressure on either side, the significant pressure is that termed the maintenance pressure, this will exist when the partition is pressurized on one side and maintenance is being carried out on the other side at atmospheric pressure.
There are designs however, where the partition is pressurized on one side and atmospheric pressure exists at all times on the other side.
In both cases the pressure to be considered on the pressurized side of the partition is the pressure at maximum ambient temperature with solar radiation effects (where applicable) and rated continuous current (where applicable).
In both cases the pressure so derived is the design pressure.
The manufacturer may if he so wishes prescribe that the pressure on the pressurized side of the partition be lowered to a specified and controlled pressure during maintenance, in such cases this pressure is the design pressure.
5.3 Stresses due to pressure
The dimension of a partition under pressure may be determined by any method using the design pressure as defined in subclause 3.1 provided the requirements of clause 7 are met.
NOTE. Pressure stresses due to an internal fault are not considered in the design of partition since after such an occurrence the partition would be carefully checked and, if necessary, replaced.
In the case of arcing due to an internal fault, the requirement of Publication HD 358 S3 (IEC 517) shall be applied.
6.1 Consultation between switchgear
manufacturer and partition manufacturer It is strongly recommended, especially when the switchgear manufacturer and the partition
manufacturer are not the same, that the switchgear manufacturer, having defined the necessary geometry and thickness of the partition,shall obtain the partition manufacturer's agreement to the design prior to casting to enable sound partitions to be produced consistently, having the required properties.
6.2 Manufacturing technique
The manufacturing technique shall be recorded by the partition manufacturer for each design of partition giving full details of method of pouring mould material, attitude of mould, temperature of moulds, curing procedure etc.
6.2.1 All subsequent production partitions shall be made by the same technique and under the same conditions without significant deviations.
6.2.2 Where the technique, material or material supplier is altered, the partition so manufactured shall be type tested in accordance with clause 7 of this standard. Production shall only proceed in the event of a successful type test.CAN CSA C50089-99 pdf download.