09419A DCN8342
Teledyne API Model 480L O
3
Monitor User Manual
21
3.4.4 MULTI-STREAM SIGNAL OUTPUTS
For instruments configured with the optional stream-selector, additional output
signals are available (see Figure 3-4).
Electrically these outputs are SPST dry contact relay closures with a common
contact. They are capable of switching up to 50 VDC, 250mA maximum current.
When relays are activated, they switch on or off any load connected to them. There
are no polarity requirements.
Table 3-4. Multi-Stream Outputs
Signal #
Function
If signal is closed
1
Stream ID
Stream X is actively being measured
2
Hi Alarm
Stream X Hi Alarm is triggered
3
Hi-Hi Alarm
Stream X Hi-Hi Alarm is triggered
3.4.5 FAILSAFE OPERATION SIGNAL AND RELAY OUTPUTS
The digital Status outputs and Alarm relays can be configured using the Failsafe
Operation variable found in the Setup>Vars menu. When the Failsafe operation has
been set to ON, the open collector transistors for the Status Outputs (Invalid
Reading, Check lamp and Pneumatic Flow) will switch to ground and become
active (Table 3-5).
Additionally, when the Failsafe Var is set to ON, the Alarm relays, HI Alarm and
HI-HI Alarm, behave the same as the System OK relay, where, in normal operating
state, the relay coils are energized and the Normally Open contact closes
(Table 3-6).
For units with multi streams enabled, the Failsafe set to ON behaves much like the
high current relays. In normal operating state without the presence of an alarm, the
coils are energized and the Normally Open contact becomes Normally Closed
Table 3-5. Status Output States - Failsafe Operation ON, No Error State Detected
Status Output
Function
Sensor OK *
Active
Invalid Reading
Active
Check Lam
Active
Pneumatic Error
Active
* Failsafe setting does not change System OK behavior.
Summary of Contents for 480L
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