Rockwell Automation 2706-P42_P43_P44_P72_P74_P92_P94 InView Marquee Message Display User Manual - Manual (Page 141)

1 Publication 2706-UM016D-EN-P - March 2006
Appendix
C
Temperature Protection in NEMA-Rated
Enclosures
Some InView signs in NEMA-rated enclosures have automatic
temperature controls that help to protect the sign from damage when
the internal temperature of the sign is too hot to continue normal
operation.
If the internal temperature of the sign reaches a pre-determined
dimming point, the LED output from the sign is forced into a 50
percent reduced power mode, effectively dimming the brightness of
LED output by about 50 percent.
If the internal temperature of the sign continues to increase, another
sensing circuit will execute an automatic shut down to protect the sign
from damage. The LED output from the sign is turned off.
The dimming and shutdown points are listed in the table below. Once
the temperature drops below the auto-shutdown threshold, the LED
output is turned on at the dimming level. Once the temperature drops
below the dimming threshold, auto-dimming is disabled and the LED
brightness is back to 100 percent.
Model Enclosure Dimming Point Auto-Shutdown On
2706-P42, 2706-P44 NEMA 2 55 °C (131 °F) 70 °C (158 °F)
NEMA 12 55 °C (131 °F) 70 °C (158 °F)
2706-P43 NEMA 12 55 °C (131 °F) 70 °C (158 °F)
2706-P72, 2706-P74 NEMA 2 55 °C (131 °F) 70 °C (158 °F)
NEMA 12 55 °C (131 °F) 70 °C (158 °F)
NEMA 4, NEMA 4x 55 °C (131 °F) 70 °C (158 °F)
2706-P92, 2706-P94 NEMA 55 °C (131 °F) 75 °C (167 °F)
TIP
Take into account the effects of ambient temperature
when evaluating mounting locations for the sign.
You should always maintain recommended clearance
distances around the sign and avoid poorly
ventilated mounting locations that could be subject
to radiation, convection, conduction or other thermal
transfer effects.