Fluke endurance series, Руководство пользователя

Страница: 67 / 102

Innovative High Temperature Fiber Optic Infrared Pyrometers
Signal Processing
55
Programming Guide
, page 73. The following figure is an example of the Deadband around a
Setpoint temperature of 960°C (1760°F).
Figure 41: Deadband Example
7.11. Outputs
7.11.1. Analog Output (current loop)
Is a current loop output circuit to drive analog output lines. It can be set to 0-20mA or 4-20mA
output current range. Direct connection to a recording device (e.g., chart recorder), PLC, or
controller is possible. The total analog output circuit im
pedance is limited to 500Ω. A 16-Bit
DAC (Digital Analog Converter) guarantees a current loop resolution better than 0.1 per
temperature unit (°C / °F) over the total measurement range. A specific feature for the testing
or calibrating of connected equipment allows the current loop output to bet set to specific values,
under range or over range in RS485 or LAN/Ethernet operation mode. Via such functionality
you can force the circuit, operating in the 4-20mA mode, to transmit an output current less than
4mA (e.g. 2.0 or 3.0mA) or above 20mA (e.g. 21.0 or 22.0mA).
7.11.2. Relay Outputs
The relay output is used as an alarm for failsafe conditions or as a setpoint relay. Please refer
to section 0
Fail-Safe
Operation
on page 81. Relay output relate to the current target temperature, displayed
on the green 7-segment LED display. The relay output can be used to indicate an alarm state
or to control external actions. The relay functionality can either be set by the control panel (user
interface), an RS485 or LAN/Ethernet command in dependence of the connected equipment to
the following states:

NO (NORMALLY OPEN)

NC (NORMALLY CLOSE)

PO (PERMANENTLY OPEN)

PC (PERMANENTLY CLOSE)
The relay states PO / PC can be used to detect wiring problems between the Endurance
®
sensor and the process environment, where the relay contact signal acts as a trigger.
7.11.3. Trigger
AVERAGE, PEAK HOLD or VALLEY HOLD can be reset by shorting the Trigger input signal to
Ground for a minimum of 10 msec. This can be done either with a momentary switch or a relay.
962°C
958°C
Setpoint: 960°C
Relay Changes State
Time
Normal State Alarm Alarm Normal State
Deadba
nd
Ob
jec
t Te
mp
eratu
re