Operation
How the Transmitter Senses the Target Gas
Ambient air surrounding the transmitter housing diffuses inside the housing where it comes
into contact with the sensor. Although the transmitter’s circuitry dissipates very little power, a
small amount of heat is produced inside the housing. This heat causes air to rise up through
the bottom vents, past the sensor, and out the upper vent. Any target gas present in this air
causes a response from the sensor. If the transmitter is located properly, the sensor will
respond to the average amount of the target gas present in the area. For help in properly
locating the transmitter, please read the mounting guidelines on page 13. This transmitter
monitors the actual concentration of the target gas exposed to the sensor. This actual value
may be different than the time-weighted-average values displayed by many personal gas
monitors. Please take this difference into account when comparing the response of the two
units.
How the Panel Controls the Ventilation Equipment
The GDCP-Touch allows the user to configure a ventilation control system in a variety of ways
to meet almost any specification. Below are the components used to build these
configurations. If requested at the time of order, Brasch will customize the configuration to
match a job requirement so that the only field work needed is installation.
Sensors
Every remote transmitter attached to the control panel contains a sensor. The
Sensor Map
tells the control panel which sensors to poll for values. Typically, this map will contain every
sensor attached to the panel, starting with Sensor 1 and ending with the highest numbered
sensor. However, during service or maintenance, it may be necessary to remove sensors.
This can be done by deselecting any sensor from the map. Thus, it is feasible to have fewer
sensors than the highest sensor number configured on the
Sensor Map
.
Relays
Every GDCP-Touch has four internal control relays with the option to add up to 32 total relays
via GDCP-ExpansionPacks. The
Relay Map
tells the panel which relays to use for controlling
equipment. Any relays that are not being used do not need to be configured. Each relay can
be set individually with unique setpoints for CO and NO
2
. Both on-delay and off-delay times
can be set per relay as well to prevent undesired relay operation. The final relay configuration
IOM03
Rev 1.1 – May 18, 2021
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