Calculating Input Shift Values For Non-Contact Sensors - Omron E5ZN Operation Manual

Shifting Input Values
4-1-2

Calculating Input Shift Values for Non-contact Sensors

1,2,3...
Figure 1 Configuration when Compensating a Infrared Temperature Sensor
One-point Shift
1,2,3...
When an ES1A Infrared Temperature Sensor is connected to the E5ZN, an
offset of several degrees to several tens of degrees can occur due to internal
impedance. Furthermore, if the rate of heat radiation of the control target is
not 0.9, errors may occur.
For this reason, offset the readout value using one-point or two-point shift as
described in this section. This offset occurs because a bias current for detect-
ing Controller sensor error flows to the output impedance of the infrared tem-
perature sensor.
Preparations
1. Set the temperature range matching the input specifications of the infrared
temperature sensor.
2. Prepare a thermometer capable of measuring the temperature of the con-
trol target as shown in Figure 1 so that one-point shift or two-point shift can
be performed.
(D) Infrared temperature
sensor
1. In the configuration shown in Figure 1, bring the SP to near the value at
which the temperature of the control target is to be controlled. Let's as-
sume that the control target temperature (C) and the control target temper-
ature (B) are the same.
2. Check the control target temperature (B) and the Controller readout (A).
Take the following value as the input shift value, and set the same numer-
ical values for both the lower limit temperature input shift value and the up-
per limit temperature input shift value.
Control target temperature (B)
Figure 2 shows the effect of one-point temperature input shift.
(C) Control target
+
(A) E5ZN
Controller readout (A)
Section 4-1
(B) Thermometer
43