52    HC900 Process & Safety Controller User and Installation Manual  Revision 6 
    21 April 2017 
Heat Rise De-rating 
The HC900 is rated to operate at 60
o 
C.  However, for maximum reliability, the following guidelines should 
be observed for applications above 52
o 
C. 
1.  Locate lower-power modules (Analog Input, Contact Input, etc) beside the Controller/Scanner Module, 
and keep higher-power modules (AC Output, AC Input, etc) away from it.  For power consumption of 
each module, see Table 4. 
2.  For 240 Vac applications and temperatures above 56
o 
C, or 264Vac, 52
o 
C, de-rate the number of ON 
inputs per AC input module. (See AC Input de-rating data, see Figure 27.) 
3.  Limit the number of Analog Output modules to a maximum of 10 per rack. (see Figure 28) 
Table 4 – Power Applied, by Module Type  
HC900 Hardware 
Power (Watts) 
Redundancy switch module (RSM) 
Power Status Module (PSM) 
Scanner 1 Port (S50/S50S) 
Scanner 2 Port (S75/S75S) 
Analog Input (High level) 
Analog Output (8 pts. internal 24V) 
Analog Output (8 pts. external 24V) 
Analog Output (16 pts. internal 24V) 
Analog Output (16 pts. external 24V)