Entering 299C Switching Devices
The following table describes the part parameters required for switching devices when 299C is the selected calculation model. The subcategories of switches supported by the 299C model are:
Basic Sensitive
Circuit Breaker
Rotary
Thumbwheel
Toggle or Pushbutton
Parameter
Type
Description
Foreign
Checkbox [Parts Count also]
Not required by the Basic Sensitive subcategory.
Indicates whether the device is made in China. If this checkbox is selected, the failure rate of the part is calculated based on Appendix A for the 299C Parts Count or Parts Stress model chosen.
Quality Level
Choice List [Parts Count also]
Not required for the Circuit Breaker subcategory.
The appropriate quality screening level of the device. Accepted quality levels and values for switches follow.
A = 0.30
B1 = 0.60
B2 = 1.00
C = 5.00
Load Type
Choice List
Not required for the Circuit Breaker subcategory. Also not required when Foreign is selected.
The type of load connected external to the device. Choices are:
Lamp
Inductive
Resistive
# of Active Contacts
Integer
Not required for the Circuit Breaker subcategory.
The number of conductive elements in the switching device that mate with another element for the purpose of transferring electrical energy.
Cycling Rate (#/day)
Real
Not required when Foreign is selected.
The average number of switching cycles per day.
Type
Choice List [Parts Count also]
Required only by the Circuit Breaker subcategory.
The type of device. Choices are:
Power Switch
Protection
# of Poles
Integer [Parts Count also]
Required only by the Circuit Breaker subcategory.
The number of poles of the circuit breaker.
[Current Parameters]
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Not required for the Circuit Breaker subcategory.
For more information, see Current Parameters.
[Temperature Parameters]
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Required only when Foreign is selected.
For more information, see Basic Temperature Parameters.
[Derating Parameters]
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For more information, see Derating Parameters.