The KLM fuse and KLM fuse holder offer no alarm detection circuitry, so the 009-8004-0100N alarm card requires voltage detection circuitry that is unique to this KLM fuse panel. If during initial power up of the input, no KLM fuses are installed the panel will enter into an alarm state resulting in a voltage across the KLM load output. This voltage is measuring the drop across two diodes in the alarm detection circuitry on the alarm card, and can measure between 1.4Vdc and 2.0Vdc.
The KLM panel's alarm card has a reset pin which brings the alarm card back to it's normal state, and when that reset is pressed it turns on an Silicon Controlled Rectifier (SCR) adjusting the current path. This change introduces an additional 1.7Vdc to 2.4Vdc drop in the voltage detection circuit.
Therefore, under normal operation, un-fused KLM outputs on the 009-8004-0100N panel should see a voltage reading between 3.1Vdc and 4.4Vdc.