VXi VT1529A/B 사용자 설명서

This connection is shown as "B" in Figure 3-1. The VT1529A/B uses 
external excitation supplies. There are four pairs of input pins (and Gnd) at 
the "Bridge Excitation" connector for up to four individual excitation 
supplies. Each of these four inputs power eight channels through a 
programmable switch. Multiple excitation inputs can be parallel-wired to a 
single power supply.

1. The excitation supply must have a balanced output with respect 

to ground. That is, the output must be centered about ground. 
For example, if the supply voltage is 5 V, then the positive lead 
should be +2.5 V and the negative lead at -2.5 V. Use of an unbalanced 
excitation supply causes longer than normal settling times in the 
VT1529A/B, which will cause errors during the measurement of the 
excitation voltage and the next few channels.

2. The maximum excitation voltage the VT1422A can sense through the 

VT1529A/B’s excitation sense path is 16 V (±8 V dc centered about 
the Gnd terminal). If a higher excitation voltage is supplied through 
the VT1529A/B, do not connect the excitation sense terminals.

3. Make sure that the power supply chosen can supply the current 

requirement of all of the bridges it can be switched to. It will be 
connected to all bridges to be measured before a measurement scan is 
started. The supply switches cannot be programmatically 
re-configured while a measurement scan is under way. The 
measurement scan must be halted to programmatically re-configure 
the excitation supply switches.