MSA Toxgard II - Isolated 4-20 Ma Output; For Signal Loads Less than 50 Ohms; For Signal Loads Greater than or Equal to 50 Ohms; Under Line-Powered Conditions

NOTE: The return path for this signal is connected to the
Toxgard II Monitor "analog common" circuitry, and
therefore, is not "isolated." The Toxgard II Monitor
can be ordered from MSA with an optional current
isolator module which fully isolates the instrument
from supplementary instrumentation.
Isolated 4-20 mA Output
• The Toxgard II current output [the (+) or upper terminal of TB1]
connects to the isolator input (+) terminal
• The Toxgard II signal return [the (-) or lower terminal of TB1]
connects to the isolator input (-) terminal.
For Signal Loads Less Than 50 Ohms:
• The user load connects to the isolator output (S) and
(-) terminals.
For Signal Loads Greater Than or Equal to 50 Ohms:
• The user load connects to the isolator output (+) and
(-) terminals.
Under Line-powered Conditions:
• The Toxgard II isolated current output
can drive a maximum load of 310 ohms (including wire).
Under Battery-powered Conditions:
• The Toxgard II isolated current output
is limited to a maximum load of 100 ohms.
Digital Output
The Toxgard II Monitor can be used as part of a Ultima Plus
high-speed digital network in order to report all internal
parameters to a central location. All that is additionally required if
this option is selected, is a network communications board and a
twisted-pair connection to the network. See Ultima Plus
instructions for complete information concerning this option.
"
WARNING
Since the Toxgard II Monitor is typically used as a safety instrument,
it is recommended that the standard and optional outputs be used
in the proper manner; otherwise, the user may not be notified of
a condition that may not be considered normal.
Make wiring connections and conduit runs according to accepted
commercial wiring practices. Install the Toxgard II unit in compliance
Chapter 1, Set-up
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