Hioki DSM-8104, Instruction Manual

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9.3 Interlock Terminal
The “INTERLOCK” connector on the rear.
Detecting open or closed state of the fixture lid, this terminal prohibits output of measuring
voltage while the lid is open to safeguard operator safety.
When using the interlock function, set the interlock function to a “Use” state on the Setup
screen.
9.3.1 Connector
Use a BNC connector.
When connecting this meter to an electrode for planar sample (SME-8310 or SME-8311) or
a shielding box (SME-8350), the interlock connecting cable (DSM8104F) is necessary.
9.3.2 Electrical characteristics
The interlock signal is output by the cathode of an LED in the photocoupler through a
current limiting resistance.
The anode side of the LED is connected to the 5V power source inside.
Output the control side output by an open collector or TTL output.
The common side (connector outer conductor) of the interlock signal is DC-isolated from the
internal circuit. The common side is connected to the input-signal common terminals (Pins
2 and 20) of the handler interface.
An equivalent circuit of the input circuit is illustrated in Fig. 9.4.
(1) Signal logic level
Measuring voltage can be output when the interlock input is the LOW level.
Output of measuring voltage is prohibited when the interlock input is the HIGH
level. (The [START] key is disabled)
(2) Electrical characteristics
Input Characteristics
Maximum Input Voltage
LOW HIGH
Maximum Input
Current
0.5 V 5 V 1.2 mA
[Caution]
Output the output of the control side by an open collector or by TTL output.
Do not impress voltage of more than 5V to input signals.
Fig. 9.4 Interlock Input Circuit