Lake Shore Model 340 Temperature Controller User’s Manual
Analog, Digital, Alarm & Relay Operation
7-5
7.3.2 Selecting an Input Alarm Source
Once an input is selected, a data
source from that input is set. The
following selections are available:
To select an input alarm data
source, press the
Alarm Setup
key.
The
ALARM SETTINGS
screen
appears with the input letter in the top left hand corner. Use the
s
or
t
key to select an input. Press the
Enter
or
Next Setting
key to show the alarm parameters for that input. Press the
Next Setting
key until the
source field is highlighted. Use the
s
or
t
key to select a source from that input. Use the
Next Setting
key to
make more changes or press the
Save Screen
key to store the changes. The default setting is Temp K.
7.3.3 Input Alarm High and Low Settings
High alarm and low alarm setting values for an input alarm are set with a 6-digit value and an additional scale
factor. The scale factor can be selected as n, u, m, k, M, and G. Blank indicates a scale factory of x1. If the
source is changed, the settings return to their default values. The instrument does not restrict the range or
resolution of the alarm setting.
To select an input alarm high or low setting, press the
Alarm Setup
key. The
ALARM SETTINGS
screen
appears with the input letter in the top left hand corner. Use the
s
or
t
key to select an input. Press the
Enter
or
Next Setting
key to show the alarm parameters for that input. Press the
Next Setting
key until the
High
or
Low
setting field is highlighted. Use the number keys to enter a value for the setting and press the
Enter
key. Press the Enter key. Use the
s
or
t
key to select a scale factor: n, µ, m, k, M, and G. Blank
indicates a scale factory of x1. Press the
Next Setting
key to make more changes, or press the
Save Screen
key to store the changes. The default values are Low = 0.0 and High = 1000.
7.3.4 Input
Alarm
Latching
To enable an alarm latching, press the
Alarm Setup
key. The
ALARM SETTINGS
screen appears with the
input letter in the top left hand corner. Use the
s
or
t
key to select an input. Press the
Enter
or
Next Setting
key to show the alarm parameters for that input. Press the
Next Setting
key until the enable field is
highlighted. Use the
s
or
t
key to turn alarm latching on or off for that input. Use the
Next Setting
key to
make more changes or press the
Save Screen
key to store the changes. The default setting is Off.
7.3.5 Input Alarm Relay Setup
The two relays on the Model 340 can be used for high and low alarm outputs. One or more sets of high and
low input alarms can be directed to the high and low relays. To direct the alarms from an input to the relays,
set the relay parameter on the
ALARM SETTINGS
screen to On. Parameters on the
RELAY & BEEPER
SETUP
screen must also be changed, as described in Paragraph 7.4.
When the alarms directed to a relay are not active (status Off), the relay is in the normal position. If any one of
the alarms directed to a relay is active (status On), the relay switches to the opposite position. Relay
connections are shown in Figure 3-7.
To direct an alarm pair to the relays, press the
Alarm Setup
key. The
ALARM SETTINGS
screen appears
with the input letter in the top left hand corner. Use the
s
or
t
key to select an input. Press the
Enter
or
Next
Setting
key to show the alarm parameters for that input. Press the
Next Setting
key until the enable relay is
highlighted. Use the
s
or
t
key to turn the relay parameter on or off for that input. Use the
Next Setting
key
to make more changes or press the
Save Screen
key to store the changes. The default setting is Off.
TEMP K
Temperature in Kelvin.
TEMP C
Temperature in Celsius.
SENSOR
Raw sensor units as read from the input sensor.
LINEAR
Linear equation output, refer to Paragraph 5.3.3.