1. One single HeatTag cannot cover an entire switchboard made up of several cubicles even without partitioning. I propose to check the installation possibilities given in the HeatTag instruction sheet at point 3 on the link below. You will also see there where to position the sensor for optimal coverage.
2. For the maximum distance for good wireless communication of PAS gateway, the document from the link below is applicable: To avoid wireless communication disturbances, the gateway and the wireless devices must be mounted with a maximum distance of 3 meters between them.
We recommend that all the wireless devices should be within the same switchboard for effective communication, please refer to the rule 1 of the generic design rules.
You can refer Rule #5 suggest to avoid wireless communication disturbances, the gateway and the wireless devices must be mounted without metallic partition between them.