Operating Instructions T401 / T402

JAQUET AG

Version 2.02

9.2.2 Signal failure

In the event of a sudden loss of a good signal no positive edge arrives to complete the measurement

or start a new one. Once the minimum measurement time (Fixtime) has lapsed the unit waits for twice the last

measurement period following which half the last measured speed is assumed.

If the signal remains missing then the measurement approaches zero following an e-function.

9.3 Functions

9.3.1 Limits and Window Function

Since the upper and lower sets points are freely selectable a large hysteresis may be set. If that is not necessary

we recommend setting a 10% hysteresis.

The Window function allows an Exclusive OR combination of Limits 1 and 2, whereby the status of both limits is

first determined (including any inversion) and a subsequent ExOR comparison executed.

As soon as Relay assignment is <Window> the relay behaves as follows:

•

With identical limit modes (both Normal or both Inverse) the relay is activated when the measured value lies

between the Limit 1 and 2 settings.

•

If different modes are set (one Normal and the other Inverse) the relay is deactivated when the measured

value is between Limts 1 and 2.

9.3.2 Parameter sets A and B

T400’s have 2 parameter sets available that define the relay assignment. Parameter set A would normally be

used. If another parameter set is needed, e.g. for test purposes, the binary input may be used to change to

parameter set B. The transfer from parameter set B to parameter set A may be delayed in the range 0 to 2000

seconds. Transferring from A to B is however immediate and not affected by this setting.

To be able to select parameter sets using the binary input, Relay control - Selection of Actuator must be

appropriately set, see 8.5.5.

Binary input condition

Selected Parameter set

High (5V) „normal“

A

Low (0V)

„connected to 0V“

B

9.3.3 Relay hold function

A latch function may be assigned to the relay. By selecting <Relay is hold if control is active> the relay is

activated once the assigned limit is active and remains held even if the input frequency would no longer cause a

trip. By selecting <Relay is hold if control is inactive>, the deactivared state of the relay is held. The latched

status may be reset by cycling power or via the binary input, whereby the binary input must be activated as per

the configuration (0V or 5V) for between 0.1 and 0.3 seconds.

9.3.4 Push-button

The front panel push button internally connects the binary input to 0VS thus generating a logic 0.