MNX10023 / Rev C
4-11-08
5
Analog Output
The analog 4-20 mA signal represents the amount of vibration energy present at
each channel based on the internal transmitter’s full scale. I.E. a 12 mA signal
from a 0
Æ
2.0 IPS transmitter represents a vibration level of 1.0 IPS.
The 4-20mA signal is wired to the terminal blocks labeled
‘4-20’
. The terminal
block marking strip identifies the individual polarity of the terminals. Each channel
provides an analog output in order to interface with an external control or
indicator. The 4-20mA signal is compatible with most PLC Analog Input Modules.
Manual adjustment of the internal transmitters may be needed upon installation.
Refer to PRO SC Transmitter user manual for specific instructions.
Example Setup 1:
A full scale range of 0 – 1 IPS has been specified. Baseline Vibration on the
machine to be monitored is 0.18 IPS-pk. Alarm and Shutdown levels of
vibration are specified as 0.35 IPS-pk and 0.65 IPS-pk respectively, reset
points are specified as 0.30 IPS-pk and 0.60 IPS-pk. Using the provided
PD765 Process Controller Manual; Select relay operation and action desired,
for this example we will have LOC, Latching Operation with Clear relays.
Then program “Set 1” as 0.35 and “Set 2” as 0.65, then program reset points,
“rST 1” as 0.30 and “rST 2” as 0.60. After relays have been programmed,
scaling must be set. For this example, we will use a 0-5 Volt input with a 0-1
IPS display. Program “inP1” as 0.00, then “diS1” as 0.00, then “inP2” as 5.00,
then “diS2” as 1.00. This will let us have an input of 0.00 Volts, display of 0.00
IPS and at an input of 5 Volts, 1.00 IPS will be displayed by the meter. The
system will now actuate the LOC Relay (Relay 1) when the vibration level
reaches 0.35 IPS-pk and another LOC Relay (Relay 2) when the vibration
level reaches 0.65 IPS-pk. In order to reset the LOC relays, the vibration level
must fall below the reset point of 0.60, then press the ACK for relay 2 and
once the vibration level falls below 0.30, press the ACK to reset relay 1.
