Lake Shore Model 218 Temperature Monitor User’s Manual
Operation
4-15
4.10 ALARM RESET
Alarm Reset
resets a latched active alarm after the alarm condition has been cleared. If the alarm
condition is not cleared, the alarm activates again during the next sensor input update cycle.
Alarm
Reset
does not affect a non-latching alarm. After pressing
Alarm Reset
, the following message
displays momentarily to confirm the reset.
4.11 RELAY SETUP (MODEL 218S ONLY)
There are eight relays on the Model 218S numbered 1 to 8. They are most commonly thought of as
alarm relays, but may be manually controlled also. Relay assignments are configurable. A relay can be
used with any input, it is not necessary for example to use relay one with input one. One relay can be
assigned to activate when either alarm from a sensor input is active or two relays can be used with one
sensor input for independent high and low operation.
When using relays with alarm operation, set up alarms first (Paragraph 4.9). The relays are rated for 30
VDC and 5 A. Their terminals are in the detachable terminal block on the Model 218S rear panel.
To begin relay setup, press
Relay Setup
. The first
display appears. Use the Data Selection keys to
cycle through the relays (1-8). Press
Enter
when the
desired relay appears.
The second display in the setting sequence appears.
Use the Data Selection keys to cycle through the
relay modes. There are three relay modes:
Off
Relay manually set to the normal state.
On
Relay manually set to the active state.
Alarms
Relay tied to alarm operation.
When the desired mode appears, press
Enter
.
Select On or Off to manually set the relay state and
return to the normal display. Select Alarm to tie the
relay to an alarm.
The third display in the setting sequence appears.
Use the Data Selection keys to cycle the sensor
inputs (
1-8
) to which the relay applies. Press
Enter
when the desired input appears.
The fourth display in the setting sequence appears.
Use the Data Selection keys to cycle through
alarms. There are three alarms:
Low
Relay active only when low alarm is active.
High
Relay active only when high alarm is active.
Both
Relay active when high or low alarm is
active.
Press
Enter
when the desired alarm appears. The normal display appears. Press
Escape
at any time
to return to the normal display. The instrument retains values changed prior to pressing
Escape
.
