Spectrum Controls 1746sc-INI4i, User Manual

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User’s Manual Pub. 0300266-04 Rev. A
Chapter 1
Module Overview
The 1746sc-INI4i monitors up to 4 isolated analog current inputs, while the
1746sc-INI4vi monitors up to 4 isolated analog current or voltage inputs
(selectable by channel). In both modules, you can select different input ranges
(for example, 4–20 mA or 1–5 Vdc) independently, by channel, for optimal use
of rack space.
Read this chapter to familiarize yourself further with your isolated analog module
(shown above). This chapter covers:
• General features and benefits.
• Detailed specifications.
Section 1.1
General Features
And Benefits
Both modules provide 750 VDC channel-to-channel isolation, which means no
electrical crosstalk between channels (resulting in less noise and a high effective
resolution). They also provide 750 VDC field wiring- to-backplane isolation to
protect your processor and other rack components. And for state-of-the-art
precision, they offer 16-bits of resolution.
For added reliability, both modules perform a battery of diagnostic tests at startup
and can alert you to open input circuits through status bits and LEDs. The open-
circuit response state is selectable. Onboard over-voltage and over-current
protection also help prevent damage to the module due to wiring errors.
Because channel-to-channel isolation is built into these modules, they eliminate
the need for expensive, external analog isolation blocks and the time and space
required to install them. Both modules provide a single-slot solution for
applications requiring up to 4, mixed, analog inputs.
They also feature auto-calibration, so you never have to perform this time-