EMS system actuator lag

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Hello,

I am attempting to simulate a ducted VRF system using the EMS system, in order to validate a building model with experimental data. I am using individual terminal units in each conditioned zone, and setting inlet conditions and cooling rates to be the same for all of the simulated units which in reality are one ducted unit. The units are controlled based on the performance of the terminal unit in the zone corresponding to the zone in the actual building that has a thermostat. I am sensing the net cooling or heating provided by the coils, and using this to calculate the PLR according to the engineering reference manual. I then overwrite the PLR of the terminal units that correspond to supply ducts from the ducted unit to simulate the actual operation. I do all of this inside the HVAC simulation. The controls are almost working, but for some reason the actuators are timestep lagging by 1 timestep. I performed a line trace using the EDD, and am looking at detailed outputs. The line trace actually seems to indicate that the PLR should be overwritten in the appropriate timestep, so I am not sure what is causing the timestep lag.

I appreciate any help including suggesting any debugging methods that I could do beyond an EDD line trace.

Thanks!