Oldham WX16, User Manual

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WX16 User Manual | 13
All relays are rated at 5 Amp for 28 VDC and 250 ~VAC RESISTIVE loads.
IMPORTANT: Appropriate diode (DC loads) or MOV (AC loads) snubber
devices must be installed with inductive loads to prevent RFI noise spikes.
Relay wiring should be kept separate from low-level signal wiring.
2.2.3 Alarm 3 / Fault Alarm Menu
The discrete channel alarms identified as Alarm 3/Fault may be configured either as a
3
rd
level alarm, or, as a Fault alarm indicating the input is out of range in the negative
direction. When used as a level alarm, features such as on / off delays, latching and
trip direction are also available. It is important to understand that though discrete
channel alarms (LED’s & optional discrete relays) may be set as Alarm 3 level alarms,
the common relay for this group is always a Fault alarm. The fault
out of range
threshold for the channel is the most recent Fault trip point entered prior to changing
the menu to Alarm 3. The following example describes how to configure both the Fault
out of range and Alarm 3 level trip points for a channel. Example: If the common Fault
relay must trip as the input falls below negative 10% of full scale, and, the discrete
alarms trip as the input exceeds a level, then the –10% Fault setpoint must be entered
first. Toggle the
TYPE menu entry to FAULT and enter –10.00% into the setpoint
entry. Next, toggle the menu back to LEVEL and enter the desired Alarm 3 level
setpoint . The -10% Fault value is retained in memory even though it no longer appears
on the menu.
Figure 2.3
2.2.4 Data From? Menu to Set Input Source
Channels may be independently configured to accept input data from the following
sources (also see Figure 2.4):
•
An analog input PCB attached to the I
2
C bus.
•
A sensor input PCB attached to the I
2
C bus.
•
The ModBus RS-485 master port connected to ModBus slave devices.
Note : Each ModBus menu selection also requests the RTU # and the Alias
register # location of the data to be retrieved from the RTU. Alias register