The CL524 indicator-simulator is a high accuracy, multifunction instrument, with two insulated, independent channels, designed to meet the needs of instrumentation engineers, in both laboratory and field work. Measuring and Simulating Functions: Both Channel 1 (Out) and Channel 2 (In) have the following operative mode capabilities:
• Millivolts
• Volts
• Milliamperes (active and passive loop)
• Ohms
• Temperature with Thermocouples
• Temperature with Resistance Thermometers
• Frequency
• Pulse Remote auxiliary inputs are available for
• Relative Humidity and Temperature

General Features
The CL524 calibrator uses innovative electronics based on a powerful 32-bit microprocessor and sophisticated high stability, low level, thermal emf-free analog circuitry. Flash memory allows firmware updating through serial interface & modem. The CL525 incorporates a real-time clock, PCMCIA memory card and improved performance.

“Help” Key
The operative set-up mode is simplified by a sequence of menu pages that require only "Select" and "Enter" instructions. A complete Instruction Manual is stored in memory for instant on-site use by the operator. Relevant instructions are accessed by using the "Help" key.

Keyboard and Display
Both the CL524 and CL525 come with a thermoformed metal-click polycarbonate membrane keyboard. The setting of the simulation signal value uses a unique in-line single-digit setting mode or a direct numeric entry mode. The high contrast LCD graphic display, equipped with a backlight device, allows easy reading, even in poor light conditions. A backlight auto power-off mode is installed to extend battery life. The graphic display allows a simultaneous indication of the measured and simulated values (in large digits), together with messages related to engineering units, types of sensor or signal, temperature scales, cold junction selection and battery level. A swap feature is installed to change the position of the IN and OUT parameters on the display.

Digital Interface
The CL524 and CL525 calibrators feature full bi-directional TTL level digital interfaces for communication with computerized systems. An RS-232 adaptor, normal or with galvanic insulation, is available on request. Firmware Firmware includes the following capabilities:
• Multiple Measurement and Generation Mode
• Signal Processing: Filter, Average, Min, Max
• Downloadable Test Procedure
• Data Acquisition
• Switch Test Routine
• Ramping and Stepping for Dynamic Testing
• User Definable Linearization
• User Entry of Probe-Specific Calibration Coefficients

Transmitter Simulation
The CL524 can be connected to system inputs to simulate 4-20 mA transmitters. It has power sufficient to drive 20 mA into a load of 1000 . in the source mode. For fast loop checks, preprogrammed steps can be recalled to output 4, 8, 12, 16 and 20 mA or % equivalent. Since the instrument has two separate channels, it is possible to read the error directly in % (In/Out). The operator can set and change temperature values while obtaining the equivalent output mA. The mA mode may be connected directly either on passive or on active loops.

Features:

• Powerful 32-Bit Microprocessor and Flash Memory for Firmware Upgrading Through Digital Interface
• All Normalized IEC, DIN and JIS Thermocouples
• Pt, Ni, Cu Resistance Thermometers for Temperature Measurement Simulation
• mA, mV, V, ., Frequency, Pulse, Counter
• IPTS68 and ITS90 Selection Directly Through Keyboard
• Current Output Mode Directly on Active or Passive Loops
• Bi-Directional Digital Interface
• Portable, Table Top and Panel Mounting
• Optional Windows 95 Software and Digital Interface
• CL525 same as CL524, but with Improved Performance and Accuracy