Spectrum Controls 1734sc-IF4U - Manual (Page 35)

Chapter 3: Configuring the 1734sc-IF4U for RSLogix 5000 3-13
User’s Manual Pub. 0300266-01 Rev. A
Channel Disable (Bit 0)
Enable (Default) = 0, Disable = 1. If the channel is disabled, all other fields are
ignored.
Filter Frequency (Bits 1 and 2)
The filter selection affects how the module attenuates the input signal at the specified
frequency. It also affects the update time of the input data which is reflected in the
minimum conversion time for each channel. Lower filter frequencies are
recommended for RTD and Thermocouple modes. The total update time for the
module can be calculated using the table below. Default setting is 17 Hz.
Table 3-2 (Channel Conversion Time)
ADC Filter
Name
(Update
Frequency)
Conversion
Time
Step Response / Module
update Rate4
470 Hz 37 ms
= Sum of conversion times for
each enabled channel 62 Hz 65 ms
17 Hz 153 ms
4 Hz 512 ms
CJC Disable (Bit 3)
When this bit is set, no CJC compensation shall be applied to the channel if it is
configured as a thermocouple. Default setting is “enabled”.
Open Circuit Response (Bits 4 and 5)
The open circuit response defines the state of the channel data when an open-circuit or
short-circuit condition is detected. Default setting is upscale.
Response
Option Definition
Upscale Sets the input data value to full-scale value. The full-scale value is
determined by the selected input type and data format.
Downscale Sets the input data value to minimum-scale value. The minimum-scale
value is determined by the selected input type and data format.
Zero Sets the input data value to zero (0).
Input Type (Bits 6 through 10)
These bits specify the input type for each channel. If channel 0 or 2 is configured
for multi‐wire RTD, the configuration for the adjacent odd channel (1, 3) is
4 The module update time is purely the sum of the conversion times for each enabled channel except
when a channel is configured for a 3-wire RTD. For each channel configured for a 3-wire RTD, double
the conversion time.