Zaxis Isaac HD, Руководство пользователя

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Flow Control Isaac has a built-in flow control to provide a slow pressure increase (ramp up) needed for burst and
crack testing. Users can precisely set the flow control for the exact pressure build-up required for the product to be
tested. After the flow control is set for a particular product, further adjustment of the needle valve is unnecessary.
Flow Standard 1) A measuring instrument or certified restrictor that can be connected to Isaac as part of a flow
calibration. The flow standard must have adequate accuracy, stability, and repeatability needed to calibrate Isaac.
The flow standard must have current calibration documentation if the customer requires accuracy traceability. 2) A
calibrated device to challenge the tester on an as needed basis. This device is calibrated and traceable. Foe
example a daily verification can be done to ensure the tester will still find the required flow value.
Flow The amount of air passing through an object measured in cubic centimeters or liters per time period (second,
minute or hour) at a given pressure.
Flow Transducer A device that converts gas flow into electrical signals. The type of transducer used in Isaac is a
mass flow transducer, which is both accurate and immune to room temperature fluctuations.
Flow Test A flow test involves pushing air through a product at a set pressure and measuring the resultant flow
with a flow sensor. Flow testing can be used in two ways--
(1) Flow Leak Detection. Product is filled with air at a set pressure and then sealed from atmosphere as in a
pressure decay test. Any flow above zero indicates a leak.
(2) Flow Measurement. Air is pushed through a product at a set pressure and allowed to flow to atmosphere. A
flow sensor measures the volume of air moving throug h the unit under test. Isaac’s digital readout shows
flow rate in customer selectable units.
Foot Switch An optional switch that connects to the back of Isaac that the operator can use to start a test cycle.
This switch has the same function as the START button on the front of the Isaac.
Gage Pressure A force referenced to barometric pressure. Isaac uses a gage regulator to keep the pressure
constant as barometric pressure changes.
Gross Leak A leak that causes a drop below the test pressure minus the pressure tolerance in the settle step.
Interface Communication between Isaac and a peripheral device such as a computer or printer. Isaac has four
interfaces, a serial protocol known as RS232 to communicate, an Ethernet port, discrete I/O points, and a
footswitch connector.
I/O (Input/Output) C onnections used Isaac to communicate with computers or Programmable Logic Controllers
(PLCs). Isaac I/O includes inputs to change and start programs and output pass/fail status.
Isaac In this guide, the word Isaac refers to the base-model Isaac leak tester. Your particular tester is based on
the Isaac leak tester and most of the contents of this guide apply.