Watlow MLS-PM, Руководство пользователя

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Introduction
MLS User’s Guide 5
Introduction
The MLS is a modular control system with 32 fully independent loops
of PID control. It can function as a stand-alone controller; the MLS
processor module's 1/8 DIN front panel has a Liquid Crystal Display
(LCD) and touch keypad for local display and local parameter entry.
You can also use it as the key element in a computer-supervised data
acquisition and control system; the MLS can be locally or remotely
controlled via an RS-232 or RS-485 serial communications interface.
The MLS features include:
Direct Connection of Mixed Thermocouple Sensors: Versatile analog
inputs let you directly connect most thermocouples. Thermocouple
inputs feature reference junction compensation, linearization, PV offset
calibration to correct for sensor inaccuracies, T/C upscale break
detection, and your choice of Fahrenheit or Celsius display.
Resistive Temperature Detector Sensors are Standard Inputs: The
standard three-wire 100 W platinum DIN curve sensor is a standard
input for the MLS, as well as the Nickel RTD.
Automatic Scaling of Linear Analog Inputs: The MLS automatically
scales linear inputs used with other industrial process sensors. To scale
inputs, simply enter any two measurement points. For example, to scale
a pH sensor enter the endpoints: the low PV is 2.0 pH, while the high
PV is 14.0 pH. All subsequent values will be in pH.
Independently Selectable PID Output Modes: You can set each loop's
digital output to ON/OFF, Time Proportioning, Serial DAC, or
Distributed Zero Crossing mode. You can set each loop control mode
for ON/OFF, P, PI, or PID control with reverse or direct action output.
Flexible Alarm Outputs: You can set independent high/low process
alarms and a high/low deviation band alarm for each loop. Each alarm
can activate an individual digital output or it can be grouped with other
alarms to activate a single digital output.
Alarm or Control Outputs: You can set high/low deviation and high/
low process setpoints to operate separate digital outputs as on/off
control functions instead of as alarms. (The control function will not
have alarm notification or global alarm output.)
Global Alarm Output: When any alarm is triggered, the Global Alarm
Output is also triggered, and it stays on until you acknowledge it.
Watchdog Timer: The MLS watchdog timer (System Safe) output
provides a digital output which notifies you if the system fails.