West Control Solutions 8700+ - Manual (Page 148)

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- DIN Controllers & Indicators - Product Manual
59305, Issue 7
– March 2014 Glossary Page 143
Loop Alarm Time Type: Controller Parameter
When On-Off control is selected and loop alarm is enabled, this parameter determines the
duration of the limit condition after which the loop alarm will be activated. It may be adjusted
within the range of 1 second to 99 minutes 59 seconds. This parameter is omitted from the
Set-up mode display sequence if On-Off control is not selected or loop alarm is disabled.
Display code =

, Default setting is 99:59.
Also refer to Loop Alarm Enable.
mADC Type: General Definition
This stands for milliamp DC. It is used in reference to the DC milliamp input ranges and the
linear DC milliamp outputs. Typically, these will be 0 to 20mA or 4 to 20mA.
Manual Mode Type: Controller Definition
If Manual Mode is enabled in Set-Up mode, pressing the AM key in operator mode will cause
a controller to enter or leave manual control mode. Switching between automatic and manual
modes is achieved using bumpless transfer.
For standard Process Controllers Manual Mode operates as follows:
The upper display shows the current process value, and the lower display shows the output
power in the form -

xxx (where xxx is equal to the percentage output power). This value
may be adjusted using the UP or DOWN keys to increase/decrease the power output. The
value can be varied between 0% to 100% for controllers using primary control only, and -
100% to +100% for controllers using primary and secondary control (e.g. full heat power to
full cool power).
For VMD Controllers with the Valve Position Indication feature Manual Mode operates as
follows:
The upper display shows the current process value, and the lower display shows the output
valve position in the form -

xxx (where xxx is equal to the amount the valve is opened,
between 0% and 100%). This value may be adjusted using the UP or DOWN keys to open or
close the as required. The Open Valve output will be energised as long as the UP key is
pressed, and the Close Valve output will be energised as long as the DOWN key is pressed.
For standard VMD Controllers without the Valve Position Indication feature Manual Mode
operates as follows:
The upper display shows the current process value, and the lower display shows

. The
valve may be adjusted using the UP or DOWN keys to open or close the as required. The
Open Valve output will be energised as long as the UP key is pressed, and the Close Valve
output will be energised as long as the DOWN key is pressed.
Manual Mode should be used with care because the power output level is set by the
operator, therefore the PID algorithm is no longer in control of the process. The operator
MUST maintain the process as the desired level manually. Manual power is not limited by the
Primary Power Output Limit.
Also refer to Bumpless Transfer, Manual Mode Enable, PID, and Primary Output Power
Limit.