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Entek IRD 6652 DSP Protection Monitor
Testing Calibration and Relays
Calibration and System OK Relay Test
The following steps show you how to test the calibration for channel 1. They also test the
function of the System OK relay. To test the calibration for channel 2, substitute the
channel 2 terminals.
1.
Connect a signal generator or other known signal source to the channel 1 input
terminals (1 and 2). Refer to “Signal Inputs for Testing” on page 40 for details.
2.
Connect a multimeter to the channel 1 4–20 mA recorder terminals (5 and 6).
3.
Set the input signal amplitude to 50% of the full scale setting for channel 1 of the
monitor. This is the FS HI 1 option on the SCALE1 submenu (page 28).
4.
Look at the 6652 DSP front panel display, and note the digital value for channel 1.
Remember that the monitor displays the channel 1 value when the indicator (a dash) is
over the channel 1 bar graph. The digital value for channel 1 should be the same as the
input signal ± 2.5% of full scale.
5.
Look at the multimeter attached to the 4–20 mA recorder terminals. The meter should
read 12 mA ± 4.5% of full scale. 12 mA is half the range between 4 and 20.
6.
Increase the input signal to 100% of the full scale setting for channel 1 of the monitor.
7.
Look at the 6652 DSP front panel display, and note the digital value for channel 1. The
digital value for channel 1 should be the same as the input signal ± 2.5% of full scale.
8.
Look at the multimeter attached to the 4–20 mA recorder terminals. The meter should
read 20 mA ± 4.5% of full scale.
9.
Decrease the input signal amplitude to 0 (zero).
10. Look at the 6652 DSP front panel display, and note the digital value for channel 1. The
digital value for channel 1 should be 0 (zero) ± 2.5% of full scale.
11. Look at the multimeter attached to the 4–20 mA recorder terminals. The meter should
read 4 mA ± 4.5% of full scale.
12. Test the state of the System OK relay terminals (25 and 26). The System OK relay is
always in failsafe conditions, so it should be in the energized (open) position.
13. Change the input signal gap voltage so that it goes outside the TX LO or TX HI limits
(“TX OK submenu” on page 30). Check to see that the TX FAIL message appears on
the monitor, and that both the display and the 4–20 mA output go to 0 (zero).
14. Test the state of the System OK relay terminals (25 and 26). The state should change to
closed when you change the input signal, indicating transducer failure. Note that the
System OK relay is not subject to the GLOBAL alarm delay (“DELAYS submenu” on
page 32).
Repeat this process for channel 2.
programmed range
0.5
×
transducer sensitivity
×
input amplitude
=
