Features and Benefits:
- 40 CFR 75 Compliant. The MASS-tron II/CEM is designed to provide all functions and meet all data reporting requirements specified under 40CFR75: signals (4-20mADC standard; 0-5V or 0-10V optional) of mass flow, temperature, and absolute pressure; daily AUTO-cal reporting of transmitter zero and span drift; daily AUTO-purge of flow sensors; AUTO-purge in progress acknowledgment; and AUTO-cal in progress acknowledgment. AUTO-cal and AUTO-purge cycles can be internally timed or externally activated, with selection via Operator set-up menu.
- Air Density Correction. The MASS-tron II/CEM transmitter is capable of performing both process temperature and process absolute pressure correction. Temperature input is an analog signal from a remote temperature device; non-linear temperature inputs can be linearized by the microprocessor. Process absolute pressure is measured by means of an internal absolute pressure transmitter connected to the transmitter static pressure signal input.
- Transmitter Hold. Certain operations performed by the microprocessor place the transmitter outputs into a “Hold” mode. This occurs when the Operator Setup menu system is accessed, when an AUTO-zero is performed, when an AUTO-cal is performed, or when an AUTO-purge cycle is in progress. When in Hold, all Normal mode processing is halted and outputs are held at their last value prior to Hold. Normal operation is indicated by the “CPU Activated” LED flashing at a rate of four times per second. A Hold mode is indicated by the “CPU Activated” LED flashing at a rate of one flash per second.
- Data Display. Integral graphical backlit LCD used during configuration/calibration and for display of process. It can display the transmitter flow, process temperature and absolute pressure signals in Engineering units, plus other signals of alarm or AUTO-cal functions, as well as user customizable tagging information. All MASS-tron II parameters and features can be configured via push-button driven menu interface via the LCD.
- Automatic Zeroing. At periodic intervals the microprocessor will automatically execute an AUTO-zero cycle consisting of the following sequence: The transmitter output and display signals are put on Hold; a valve is activated which disconnects the process high pressure from the high port of the transducer and connects the process static pressure to both sides of the transducer, creating a true zero differential pressure; after a brief stabilization period, the transducer zero offset signal is measured and stored in memory; the valve is deactivated and after a brief period for process signal stabilization, the Hold is released and Normal process measurement resumes. During Normal operation, the zero offset value stored in memory is subtracted from subsequent transducer readings until the next AUTO-zero cycle occurs and repeats the process. AUTO-zero On/Off and Interval are available and configurable using the Operator Setup menu.
- AUTO-cal to measure transmitter zero and span drift. The AUTO-cal cycle is initiated at 24-hour intervals, in user-programmed intervals, or when externally activated. During the cycle, the display and all outputs remain constant (Hold) which creates a zero differential pressure across the transducer. Any zero signal error is measured and stored. Upon completion of the AUTO-zero cycle, the MASS-tron II/CEM performs an AUTO-span cycle which creates a percent of full scale differential pressure across the transducer. Any span signal error is measured and stored. The remainder of the AUTO-cal cycle consists of: Start Report Delay; Zero Report Duration, In Between Report Duration; and Span Report Duration – all of which have user selectable durations.
- Alarms. The MASS-tron II/CEM Alarm Option provides the means for having the process signal compared to a user selectable Low Flow alarm point and automatically activates a Form C relay to generate a dry contact alarm signal. Alarm On/Off, Setpoint, Dead Band, and Delay are configurable via the Operator Setup menu. Alarm Setpoint can be displayed on during Normal operating mode. An Alarm Delay is available, if implemented (any time setting greater than zero), any condition that would normally cause an alarm, triggers the delay timer first. If the alarm condition still exists after the delay times out, then the alarm relay is activated.
- Flow/Differential Pressure Calculator. The MASS-tron II/CEM is equipped with an integral calculator feature that allows the user to determine the maximum flow or differential pressure from the appropriate variables. This feature allows the user to determine input or output values at various points of the process or new values if the process parameters have changed. Also, the calculator can be used to implement a single-point density compensation for operating temperature and/or absolute pressure.
- K-Factor. The MASS-tron II/CEM is equipped with a K-Factor feature which allows for the introduction of a bias and/or gain factor into the transmitter’s flow calculations. The K-Factor feature is intended to be used in two types of applications: (1) To adjust for flow measurement error as a result of highly distorted airflow induced by upstream or downstream flow disturbances. (2) To adjust the transmitter’s output to bring it into close correlation with field measured flow data. The K-Factor gain and bias values can be entered directly or the MASS-tron II/CEM can calculate these values based on measured and reference values from a single or multiple load point airflow traverse.
- User-selectable primary signal noise filter
- Input power isolation
- Capability of 10:1 flow or 100:1 pressure turndown
- 19” Rack Mount