TESTO 6681 Profibus, Instruction Manual

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testo 6681
- 1.2 Product description 11
•
12 terminals for a total of 4 relays.
If no relays are available, settings for monitoring limit values
or alarms can still be controlled via the display. The alarm
status will be shown on the display
Only have the transmitter wired and connected by authorized
personnel with the voltage disconnected.
1.2.6 Analog outputs
For analog outputs, the testo 6681 has either
•
2 or optionally 3 current outputs of 4 to 20 mA (2-wire)/0 to 20 mA (4-
wire)/4 to 20 mA (4-wire) or
•
2 or optionally 3 voltage outputs of 0 to 1 V/0 to 5 V/0 to 10 V (4-wire).
The transmitter can be ordered with a third analog output as an option.
In 2-wire operation, channel 1 is used for the supply. The two or optionally
three channels are galvanically isolated in both 2- and 4-wire operation.
Operation with the testo 6614 heated probe, the testo 6615
trace humidity probe, the relay option or with the background
lighting of the optional display are only possible in 4-wire
operation.