User Guide
Doc# A824D001 v2.0
15-Nov-2018
Page 13 of 28
PI (Physik Instrumente) L.P.
16 Albert Street, Auburn, MA 01501
Tel: 508-832-3456 Fax: 508-832-0506
Email: [email protected]
The Interlock cable which connects the air pressure switch on the air prep kit (if purchased) includes a 2-pin
connector (Molex Part# 43640-0201) that can be used by the end user to connect additional interlock devices.
The two pins can be connected in series to various 24 VDC devices, such as E-stop switches, door switches,
light curtains, etc. Integrating these functions is the decision and the responsibility of the user.
The Interlock cable is shipped with a bypass jumper installed. If the jumper is installed, the user interlock is
bypassed, and only the air pressure switch is used by the controller’s interlock circuit.
Figure 4 - Interlock Bypass Jumper
To completely bypass all interlock functionality of the A-824, c24VDC to the INTLOCK1 pin on the A-
824
’s Interlock connector.
8. Connecting the Controller to Protective Earth
To minimize the possibility of bodily injury or death from electric shock in the case of malfunction or
failure of the system, make sure a protective earth conductor is properly connected.
The A-824 has two (2) M4 threaded studs for connecting the controller chassis to a protective earth ground
conductor. The studs are marked with the symbol for the protective earth ground and are located on the rear
panel of the controller near the upper corners.
Figure 5 - Chassis Protective Earth Stud Location
The fasteners needed to attach a protective earth conductor are included with the A-824, with a full set
mounted to each ground stud.
The protective earth conductor cable cross-section should be
≥0.75 mm
2
(20 AWG or heavier).
