Model 2790 SourceMeter® Switch System User’s Manual 5-9Interlock connections:Figure 5-6 — When using a test fixture or safety shield that has an interlock switch, con-nect interlock as shown in Figure 5-6.Figure 5-6Interlock connectionsInterlockNOTE An enabled interlock allows the I-source and V-source (7751/7753) to be con-nected to the rest of the switch matrix. An open (disabled) interlock does not dis-able the sources. The sources are always on and available at the J107 terminalsof the module. Interlock has no effect on the source outputs at J107.The selected source can also be accessed at J105 (Source Hi and Source Lo)when interlock is enabled. With interlock open, the sources are disconnected.The interlock of the 7751/7752/7753 module must be enabled in order to connect theI-source or V-source (7751/7753) to the rest of the switch matrix. With interlock disabled,you will not be able to close switches that connect the selected source to the DUT and DMM.The typical test station has a built-in interlock switch, which is to be connected toINTERLOCK of the 7751/7752/7753. When the test station lid or safety shield is open,the switch will open to disconnect the sources of the 7751/7752/7753.Figure 5-6 shows how to connect the interlock of the 7751, 7752, or 7753 to the test station.+5VINTERLOCKJ106Lid/shield open = switch open = Sources disconnectedLid/shield closed = switch closed = Sources connectedConnect to safety earthground using #18 AWGwire or larger.Test StationINTERLOCK DO NOT permanently short out the interlock.Interlock is an essential safeguard to preventpersonal injury due to electric shock and/oraccidental ignition of an inflator.It is a good safe practice to use an interlocktest station that always disables the sources andprovides protection from inflator ignition.WARNINGKeithley 7751, 7752, or 7753
