External Start Signal I/O (Meas Start) - YOKOGAWA WT1800 User Manual

4.4

External Start Signal I/O (MEAS START)

• If you have set the WT1800 as the master unit, do not apply an external voltage to the
external start signal I/O connector (MEAS. START). Doing so may damage the WT1800.
• If you have set the WT1800 as a slave unit or set External Sync to ON in high speed data
capturing mode, only apply signals to the external start signal I/O connector that meet the
following specifications. Signals that do not meet the specifications, such as those with
excessive voltage, may damage the WT1800.
External Start Signal I/O Connector
To Apply a Master/Slave Synchronization Signal during Normal
Measurement
Connect the external start signal I/O connectors on the rear panels of the master and slave instruments
using a BNC cable (sold separately).
Item
Connector type
I/O level
Output logic
Output hold time
Input logic
Minimum pulse width
Measurement start delay
Note
The measurement of the master and slave units cannot be synchronized under the following conditions:
• When the data update interval differs between the master and slave.
• In real-time integration mode or real-time storage mode.
Follow the procedure below to hold values during synchronized measurement.
• To hold values:
• To stop holding values: Stop holding values on the slaves first.
To Apply a External Synchronization Signal during High Speed
Data Capturing
Apply a external synchronization signal that meets the following specifications to the external start
signal I/O connector (MEAS START) on the rear panel.
Item
Connector type
Input level
Input logic
Minimum pulse width
Measurement start delay
IM WT1801-03EN
CAUTION
Specifications
BNC connector
TTL (0 to 5 V)
Negative logic, falling edge
Low level, 500 ns or more
Negative logic, falling edge
Low level, 500 ns or more
Within 15 sample intervals
Within 1 μs + 15 sample intervals
Hold the values on the master first.
Specifications
BNC connector
TTL (0 to 5 V)
Negative logic, falling edge
Low level, 500 ns or more
Within 1 μs + 15 sample intervals
Notes
Same for both master and slave
Same for both master and slave
Applies to the master
Applies to the master
Applies to slaves
Applies to slaves
Applies to the master
Applies to slaves
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App
Index
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