User manual

User Manual – Rev B FCS Series II
2.6.4 –EXS Option - Supplemental Specifications
The –EXS (External Sync) option allows the output frequency of the AC source to be synchronized to an
external TTL level clock signal.
The following supplemental specifications apply when the FCS II is configured with the external sync option.
(-EXS).
Parameter Supplemental Specification
Input
Voltage Input TTL Level square wave.
Impedance 10 KOhm.
Frequency
Range Same as internal clock mode. See configuration limits.
Max Sync Input Slew Rate < 80 Hz / sec.
Changes in sync input frequency occurring faster than this rate will result in
Error 804: External Sync Error. Output relay is opened on Error.
Max Sync Step < 20 Hz.
Sudden changes in sync input frequency greater than 20 Hz will result in
Error 804: External Sync Error. Output relay is opened on Error.
Mode Selection
When switching between INT and EXT sync mode, the output of the AC
source will be dropped momentarily.
Restrictions
Frequency cannot be programmed in external sync mode.
Frequency transient list system is not available in sync mode.
Transient list dwell times are not correlated to external sync but based on
internal timebase.
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