Clear, Accurate Readout
Sharply defined graduations, a 45-inch (1140 mm) scale length over two pointer revolutions, and a knife-edge pointer facilitate precise readouts. All scale calibrations are individually plotted and hand marked to produce a dial custom fitted to the pressure element and mechanism of that gauge.
Engineered for Performance
The gauge housing is heavy cast aluminum with a tempered glass dial cover. A built-in pressure-relief valve has a dumping capacity which protects the case against overpressures to 10 times the maximum pressure rating. A separate pressure-relief valve protects the capsule mechanism. The gauge ismounted inside the carrying case on rubber-padded shock mounts. The carrying case is constructed of strong but lightweight molded ABS that flexes to absorb shock from impact.
Compact, Built for On-SIte Service
The WIKA Portable Pneumatic Calibrator weights only 20 lb (9 kg) and is only slightly larger than a attache case. The easyportability, simple set-up, and the versatile capabilities of this unit extends its usefulness for service in the field. Its portability saves the time and expense of shop calibration.
Standard Ranges and Ordering Numbers
The standard scale contains two sets of calibrations (dual scale) in the pressure units inches of water and psi. Dial markings in the negative range are in red colour and in the positive range in black colour.
Design and Construction
The Series 65-120 Portable Pneumatic Calibrator is a pressure-vacuum test stand wholly contained in a carrying case. The front panel accommodates the precision pressure gauge, all pressure connections, two air-regulator controls, and a selector valve. With the selector valve, three different test pressures can be applied individually to the gauge. A fourth selector setting vents the gauge to atmosphere.
The precision pressure gauge has a Ni-Span C, capsule-type pressure element which gives excellent temperature stability and speed of response. An almost frictionless mechanical linkage amplifies capsule movement and transmits it to the pointer. Although highly sensitive and accurate, the mechanism is built to withstand the handling normallyassociated with on-site calibration of pneumaticinstrumentation.
A filter on the air supply keeps oil and moisture out. Two regulators apply known pressures to the devices under test. The connection block has ⅛-inch female-pipe-threaded connections. Small gauges can be threaded directly into the block; or as with larger instruments, connected by flexible tubing.
The standard scale contains two sets of calibrations:– 100 to 0 to 850 inches of water (20 ºC) and – 3.6 to 0 to 30.6 psi.Other ranges and units of calibration (from min. 0 – 4.5 psi to max. 0 – 100 psi) are available.
Connections for Different Pressure Readouts
- For gauge pressure: test pressure is applied to the capsule through the appropriate P connection; the case is open to atmosphere through S.
- For differential pressure: high test pressure is applied to the capsule through the appropriate P connection. Low test pressure is applied to the case through S.
- For absolute pressure: test pressure is applied to the capsule through the appropriate P connection and the case is continuously subjected to full vacuum through S.
- For vacuum: the capsule is open to atmosphere through connection P; the case is connected to test vacuum at S.
- For positive and negative pressures: test pressure is applied to the capsule through theappropriate P connection and the case is open toatmosphere through S.
The WIKA Portable Calibrator eliminates the need for special arrangements or external controls. The carrying case has a compartment for adapters, tubing, and other accessories; the case cover is easily removed. Complete information on the use of the calibrator is given in an instruction book. A schematic flow diagram on the panel shows the calibrator’s connections at a glance.
Simplest use of the calibrator is to carry it to an onstream gauge, indicator, or recorder. Calibration of such instruments can be quickly checked by making simple connections without taking the instrument out of service. Also, the calibrator can simulate the set and process-variable signals to a pneumatic control device and check its output. These three pressures can be read out and checked in any order and in rapid sequence. By evacuating the calibrator, absolute pressure measurements can be made.