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Haiwell PLC - Temperature & Humidity Module Application Case
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Temperature & Humidity modules Application Case
1. Expand module through the host PLC parallel port
1.1 Module power supply
Haiwell temperature and humidity module can be the expansion module for any host PLC; When the module is directly hung
behind the host PLC by parallel bus, no need to take external power supply, the module is powered by host PLC’ parallel port, if
the power supply of module is insufficient (the PWR power indicator does not light), then according to different models, the module
can be powered by 24VDC or 220VAC. When the module is extended through the parallel port, it is recommended to use 24VDC
module. Module power supply example:
1
When the host PLC can be expanded to 7 modules, the PWR indicators of frist five modules are long bright, indicating the
modules power supply are normal, and if the PWR indicators of the 6th and 7th modules are not light, appearing
insufficient power supply, as long as the 6th and 7th modules are taken external power supply.
2
When the host PLC is connected with 1 expansion module, because the host PLC provides power supply through the
parallel port, the PWR indicator of modue will light; If the module is added external power supply, it can still work, this time
the module will automatically determine and give priority to external power supply.
1.2 Temperature modules need't be written any conversion program, read the current temperature value directly when access
the sensor
For example, the host PLC T16S2T, respectively, is expanded with three modules of H04TC, H04RC and H08TC through the
parallel port from left to right, assuming the scene:
Thermocouple module H04TC input channel 1, signal type is K, input channel 2, signal type is E;
Thermal resistance module H04RC input channel 1, signal type is PT100, H04RC input channel 2, signal type is PT1000;
First enter the PLC programming software menu bar - view - hardware configuration, in accordance with the external order of
actual modules to add the module models, after added, the analog addresses will be automatically arranged, as shown below:
Haiwell temperature and humidity module need't be written any conversion program, for the above measuring temperature, we
only need to select the corresponding channel signal type, check the use of engineering value and full index number by default,
for example, the above module H04TC input channel 1, the signal type is K; the input channel 2, the signal type is E, as long as
we set the hardware configuration:
In this way, after configuration, as long as connect the K-type thermocouple to channel 1, then directly read AI0 register value, AI0
