Switching between a Remote & Local Setpoint with a Digital Input.
Solution: Specify a UDC 3500 with a Digital Input Option.
When a digital input is configured for To LSP, the UDC will switch from Remote SP to a Local SP with a contact or switch closure.
Configuration:
1.Setup – Control – RSP SRC is set to Input 1, 2, 3, 4, 5, IN ALG 1 or IN ALG 2.
2.Setup – Option – DIG INP 1 2, 3 or 4 is set to LSP
Operation:
1.Make sure that the Digital Input Switch is open and Remote SP is selected
2.Set the desired setpoint for Local SP using the Lower Display & arrow keys.
3.With the Digital Input Switch closed, SP will be displayed on the Lower display.
4.When the Digital Input Switch is re-opened the bar next to the left of the RSP will light, and the Remote SP will be the controlling setpoint.
Notes:
1.If the Setpoint Select is enabled, then someone can override the Digital Input by pressing the SP Select key.
A suggested correction is, prior to doing step 3 in the operation section, go to Tuning Group and set the Lockout to None. Keep pressing the Function key until SP SEL appears in the lower display. Set the Upper Display to DISABLE.
With the Setpoint Select set to disable, the unit can not be switched to Local SP by the keyboard.
2.A different set of Tuning constants can be selected when Local SP is selected. If Two sets of Tuning constants are selected under the Control section, then by using the DIG 1 CMB or DIG 2 COMB set to +PID 2 then PID set 2 tuning values will be used when SP is selected.
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