Delta OHM HD45 17A, Manual

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• Simplified mode: the relay functions with a single threshold, that can be selected
from a series of fixed values via a rotary switch.
• Complete mode: the relay may function with one or two thresholds that can be
freely set via a PC.
Toggling between the two modes is made by means of a rotary selector placed on the
instrument electric board, between the terminal board and the mini-USB connector.
Fig. 4.C: Rotary selector position
The selector has ten numbered positions ranging from 0 to 9.
If the selector is in position 0 (default setting), we are in complete mode and the
instrument operates with thresholds and hysteresis set via software (see Tab. 4.B for
factory settings).
Tab. 4.B: Relay output default settings in HD45 models
Temperature (HD45 17…R and HD45 7B…R) CO
2
(HD45 B…R)
Threshold = 100.0 °C Threshold = 1000 ppm
Hysteresis = 5.0 °C Hysteresis = 100 ppm
If the selector is in a position other than zero, we are in simplified mode: the relay
activates only on the threshold set with the rotary selector.
If the selector is associated with the CO
2
measurement, each position corresponds to a
threshold value according to the table below:
Tab. 4.C: CO
2
threshold rotary selector
POSITION CO
2
RELAY THRESHOLD (ppm)
0 Rotary selector disabled
1 600
2 800
3 900
4 1000
5 1200
6 1400
7 1600
8 1800
9 2000
If the selector in a position other than zero, hysteresis is preset to 100 ppm.
Hysteresis and intervention mode can be changed via software (see section
Mini-USB
connector
Rotary
switch
Terminal board