Application Examples - Description - Phoenix Contact ELR W3- 24DC/500AC-2I Manual Del Usuario

4.3.1. Error acknowledgment
Three separate options are available for the error acknowledgment:
Manual (reset button): An acknowledgment is triggered by activating the reset button on the front of the
device.
If the reset button is still activated after the end of approx. 2 s, the solid-state reversing contactor will return
to the error state. If the acknowledgment request (activated reset button) is present longer than 6 s, an
expanded test of the power output module is carried out and then changes to the operating mode
"Parameterization".
Manual (remote acknowledgment): A remote acknowledgment control point can be implemented by
connecting a button (N/O contact) between the MAN (2.1) and RES (2.2) terminals. An acknowledgment
is triggered as soon as a positive edge is detected at the MAN input. If a negative edge is not detected
after the end of a period of approx. 2 s, the solid-state reversing contactor will return to the error state,
since a manipulation or a defect in the acknowledgment circuit cannot be excluded.
Automatic: If an electrical connection is created between the RES (2.2) and AUTO (2.3) terminals, the
device carries out an automatic acknowledgment after tripping the bimetal monitor.
4.3.2. Feedback
As soon as the solid-state reversing contactor detects an error, the acknowledgment relay is activated,
i.e. the N/O contact will be closed and/or the N/C contact is opened. This response corresponds with that
of a motor protection switch or a motor protection relay.
The acknowledgment only serves for signaling and is not a part of the safety chain. It is therefore not
included in the safety observation.
5. Application Examples
5.1. EMERGENCY STOP
The easiest form of the integration of an solid-state reversing contactor into an EMERGENCY STOP chain
is illustrated in Fig. 3 (page 52). The rated control supply voltage is disconnected by a safety relay within
this context, as soon as the EMERGENCY STOP button is activated.
Switching off the motor voltage is assured 25 ms after switching off the rated control supply voltage. Since
the operating voltage of the solid-state reversing contactor is switched off only at a single channel, this
type of installation according to SIL 3 (cat. 3, cat. 4) is only permitted when a fault elimination is allowed
for the cross-circuit, as is the case when the solid-state reversing contactor and the safety relay are
installed in the same control cabinet.
If such a fault elimination is not permitted, the rated control supply voltage must be switched off via two
channels or two positions (refer to Fig. 4, page 53).
However, this type of integration requires that switching off the rated control supply
voltage of the activated motor is always connected with wear in the solid-state reversing
contactor. Both control circuits should therefore only be used, if no more than 10,000
disconnections are anticipated over the entire service life of the system!
5.2. Safety door (EMERGENCY STOP and EMERGENCY OFF)
A circuit according to Fig. 5 (page 54) and Fig. 6 (page 55) should be used in applications in which the
safety switch-off is a normal operating state, such as in the safety door or in two-hand applications.
Not the rated control supply voltage but the control circuit is switched in this application. Single channel
as well as two channel applications can be implemented. For this purpose, the supply line of the right or
left rotation activation and the appropriate mass must be supplied via the safety relay.
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