Server Technology C-16HF1-C20 - Manual (Page 8)

8
• Operations Rack-Mount Fail-safe Transfer Switch
Installation and Operations Manual
Chapter 3: Operations
Modes of Operation
The Sentry Rack-Mount Fail-Safe Transfer Switch is designed to operate in the following modes:
• Normal
Infeed A provides power to branches A1 & A2 and Infeed B provides power to branches B1 & B2.
Each infeed is monitored individually for voltage and current.
• Input Failure
The equipment powered by the failed input is transferred to the remaining input. The input current
LED display of the failed input will be blank and the remaining display will report the total current
load for the unit.
• Recovery from Input Failure
When voltage is restored to the failed input and remains within ±7% of nominal for 2 seconds, the
equipment normally supported by that input is transferred back returning the Sentry to a ‘Normal’
mode with the input current LED displays reporting the total current load for each respective
infeed.
• Brownout/Over-Voltage
When an input’s voltage varies from its nominal by ±13% or more, the equipment powered by that
input is transferred to the remaining input. The input current LED display of the input in the
brownout/over-voltage state will be blank and the remaining display will report the total current
load for the unit.
Nominal Voltage * Brownout Recovery Voltage Over-Voltage
100V 87.0V 93.0V 107.0V 113.0V
110V 95.7V 102.3V 117.7V 124.3V
115V 100.0V 106.9V 123.0V 129.9V
120V 104.4V 111.6V 128.4V 135.6V
208V 181.0V 193.4V 222.6V 235.0V
220V 191.4V 204.6V 235.4V 248.6V
230V 200.1V 213.9V 246.1V 259.9V
240V 208.8V 223.2V 256.8V 271.2V
* Nominal operating voltage is configured by the Voltage Selector Switch.
• Recovery from Brownout/Over-Voltage
When the input’s voltage returns to and remains within ±7% of nominal for 2 seconds, the
equipment normally supported by that input is transferred back returning the Sentry to a ‘Normal’
mode input current LED displays reporting the total current load for each respective infeed.
• Critical Brownout
A critical brownout is when an input’s voltage drops below its nominal by -25%.
• When an input is already in a brownout/over-voltage state AND the remaining input
experiences a critical brownout, ALL equipment will be transferred to the input only
experiencing a brownout/over-voltage.
• When an input has already failed AND the remaining input experiences a critical
brownout, ALL outlets will turn off.
• Recovery from Critical Brownout
When the input’s voltage returns to and remains within ±7% of nominal for 2 seconds, the
equipment normally supported by that input is transferred back.