Honeywell VRX180 user manual Type J Thermocouple

Programming and Operating Concepts

TYPE J

THERMOCOUPLE

				AO1 BC
	AI1 OV
AI1			FB
			PV	LP1 OV		4 TO 20 mA
			LP1
					IN AO1
INPUT TYPE = J			SP2
RANGE LOW = 0
RANGE HIGH = 1000			TYPE = STANDARD		OUTPUT TYPE = CAT
			SP1 = 500		IN LOW LIMIT = 0
			SP2 = SP1 OV		IN HIGH LIMIT = 100
			GAIN = 10		OUT LOW LIMIT = 4
			RESET = 1		OUT HIGH LIMIT = 20
		SP1 OV	RATE = 0
SP1

Figure 3-24 Function Block Diagram Of Set Point Profile Control Of Figure 3-16

Figure 3-24 basically depicts all the components of the Figure 3-16’s control configuration with a set point profiler function block denoted by SP1. The profiler’s output (SP1 OV) is connected to the remote set point input of LP1. Depending on the model number of the instrument, up to four set point profiler function blocks (SP1 through SP4) may be included within the instrument’s feature capacities. Note that while the profiler of SP1 was specified in Figure 3-24’s diagram, any of the profilers within the instrument could have been used.

When a set point profile is executed, discrete inputs are typically used in conjunction with external switches to control the set point profiler function block. For example, the set point profiler function block can be programmed to start, hold, or reset based on discrete input statuses. See Figure 3-25.

TYPE J

THERMOCOUPLE

External

Switches

DI1

DI2

DI3

						AO1 BC
		AI1 OV
	AI1				FB
					PV	LP1 OV		4 TO 20 mA
					LP1
							IN AO1
	INPUT TYPE = J				SP2
	RANGE LOW = 0
	RANGE HIGH = 1000			TYPE = STANDARD			OUTPUT TYPE = CAT
DI1 OS				SP1 = 500			IN LOW LIMIT = 0
				SP2 = SP1 OV			IN HIGH LIMIT = 100
				GAIN = 10			OUT LOW LIMIT = 4
				RESET = 1			OUT HIGH LIMIT = 20
	START		SP1 OV	RATE = 0
DI2 OS
	HOLD SP1
	RESET
DI3 OS

“OS” = OUTPUT STATE

Figure 3-25 Discrete Inputs Controlling Execution Of Set Point Profiler Function Block

Video Recorder – User Manual 71