Allen-Bradley micrologix 1500, User Manual

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Publication 1764-UM001A-US-P
Glossary 5
QRUPDOO\ FORVHG
Contacts on a relay or switch that are closed when the relay is de-energized or
deactivated. They are open when the relay is energized or the switch is activated.
QRUPDOO\ RSHQ
Contacts on a relay or switch that are open when the relay is de-energized or the
switch is deactivated. They are closed when the relay is energized or the switch is
activated.
RIIGHOD\ WLPH
The OFF delay time is a measure of the time required for the controller logic to
recognize that a signal has been removed from the input terminal of the controller.
The time is determined by circuit component delays and by any applied filter.
RIIOLQH
When a device is not scanning/controlling or when a programming device is not
communicating with the controller.
RIIVHW
A continuous deviation of a controlled variable from a fixed point.
RIIVWDWH OHDNDJH FXUUHQW
When a mechanical switch is opened (off-state), no current flows through the
switch. Semiconductor switches and transient suppression components which are
sometimes used to protect switches, have a small current flow when they are in the
off state. This current is referred to as the off-state leakage current. To ensure
reliable operation, the off-state leakage current rating must be less than the
minimum operating current rating of the device that is connected.
RQGHOD\ WLPH
The ON delay time is a measure of the time required for the controller logic to
recognize that a signal has been presented at the input terminal of the controller.
RQH VKRW
A programming technique that sets a bit ON or OFF for one program scan.
RQOLQH
When a device is scanning/controlling or when a programming device is
communicating with the controller.
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For inputs, the voltage range needed for the input to be in the On state. For
outputs, the allowable range of user-supplied voltage.
RXWSXW GHYLFH
A device, such as a pilot light or a motor starter coil, that receives a signal or
command from the controller.
AB Spares