Future Design MCT-CM, Руководство пользователя

Страница: 36 / 247

MCT-CM
36
3.5.1 Thermocouple Module (IO-8TCS) Input Wiring
The IO-8TCS is an 8 isolated thermocouple input module. The module uses differential inputs to reduce effects
of electrical noise. The thermocouple inputs are isolated from the internal logic and from each other. The
module has built in cold junction compensation. Be sure to use the correct thermocouple extension wire to
avoid reading errors.
DIP switch 9 is used to select upscale or downscale burnout. A value of 32,768 is used to indicate upscale
burnout and a value of
–32,767 is used to indicate downscale burnout. When DIP switch 9 is turned on, the
module will use the upscale burnout value and when turned off, the module will use the downscale burnout
value.
NOTE: DIP switch 8 is not used with the thermocouple module so its position does not affect operation.
3.5.2 Current (IO-8AIIS) and Voltage (IO-8AIVS) Module Input Wiring
The analog input modules are supplied as either a current input module (IO-8AIIS) or a voltage input module
(IO-8AIVS). The inputs are fully isolated from the internal logic and between inputs. The standard setting for
the IO-8AIIS module is 0-20mA input current which represents the minimum to maximum range setting in the
MCT. To obtain an input signal of 4 to 20mA the offset switch, DIP switch 8, must be switched on.
The same applies to the IO-8AIV module. An input voltage of 0-10Volts represents the minimum to maximum
range setting in the MCT. To obtain an input signal range of 2 to 10V the offset switch, DIP switch 8, must be
switched on.
NOTE: DIP switch 9 is used to select upscale or downscale failure when the input signal is too far above or
too far below the selected input range. A value of 32,768 is used to indicate upscale failure and a
value of
–32,767 is used to indicate downscale. When DIP switch 9 is turned on, the module will use
the upscale failure value and when turned off, the module will use the downscale value.