National Instruments 1128 用户手册

© National Instruments Corporation

The SCXI-1127 and SCXI-1228 modules are high-voltage 
multiplexer/matrix modules. The SCXI-1127 is a high-density armature 
relay module. The SCXI-1128 is a high-density solid-state relay module. 
Both modules provide a 1 

× 32, 2-wire multiplexer and several switch 

matrix configurations on an SCXI platform. The SCXI-1127/1128 can also 
operate as two 1 

× 16 or four 1 × 8, 2-wire multiplexers (in independent 

mode) allowing a single module to handle several multiplexing needs.

Through software-configurable switches, the module can also operate as a 
1-wire 1 

× 64 multiplexer, enabling you to make a large number of common 

referenced measurements. It can also operate as a 1 

× 64, 4-wire 

multiplexer to make resistive measurements such as those needed for 
thermistors and RTDs. With the use of special terminal blocks, the 
SCXI-1127/1128 can become a 4 

× 8 or 1 × 32, 2-wire matrix. A complete 

list of possible configurations is given in Table 1-1.

To handle large channel counts, you can expand the size of the multiplexer 
with additional SCXI-1127/1128 modules. These modules support the 
analog bus through a special adapter, the high-voltage analog bus (HVAB) 
backplane adapter in the SCXI-1357/1358 kit, at the rear of the module. 
This adapter allows you to expand the HVAB without complicated wiring. 
For example, you can connect two SCXI-1127/1128 modules using the 
HVAB-backplane adapter to create a 1 

× 64, 2-wire multiplexer.

Table 1-1.  SCXI-1127/1128 Configurations

1-wire

1 

× 64

N/A

2-wire

1 

× 32

4 

× 8 (also 2 × 16, 1 × 32)

4-wire

1 

× 16

N/A