The two 4 to 20 mA DC output channels are capable of driving into a 1000Ω load.
Channel 1
(Oxygen %)
Load
Connect a maximum
load of 1000 ohms.
Output is 4 to 20mA
DC isolated.
Channel 2
Load (optional)
CH1 O/P+
CH1 O/P-
CH2 O/P+
CH2 O/P-
27
28
25
26
Figure 3.4 Connections for Transmitter Output Channels.
3.4 CONNECTING THE ALARMS
A common alarm, which should be connected for all installations initiates on alarms functions described below. Three
additional alarm relays are available for selectable functions as listed in Section 4.2 and 4.3. Each relay has normally
closed contacts. The contacts will open in alarm condition except for the optional horn function which operates with
normally open contacts. Relays are connected as follows:
Relay Terminal Numbers
Common Alarm 29 & 30
Alarm 2 31 & 32
Alarm 3 33 & 34
Alarm 4 35 & 36
Common Alarms All of the following conditions will cause a common alarm -
ADC Calibration Fail
DAC Calibration Fail
Oxygen Sensor Fail
Oxygen Heater Fail
Oxygen Sensor TC Open
Gas Pump Fail
Mains Frequency Check fail
Oxygen Gas Calibration Check Error
Carbon Dioxide Sensor Fail
Watchdog Timer
The watchdog timer is a special alarm. It will force the common alarm to activate in the event of a microprocessor
failure. There will not be an alarm message displayed, but the Analyzer will reset.
Alarms can be accepted by either pressing the alarm button (viewing the alarm messages), or by temporarily closing a
switch connected to terminals 16 & 17, REM ALARM RESET.
Alarm relay 2 to 4 Select any one or all of the following for each relay. Refer to Section 5.5, steps 45 to 47
High oxygen
Low oxygen
Very low oxygen
Oxygen sensor under temperature
Calibration check in progress
Alarm horn function (Relay 4 only)
3.5 CONNECTING THE HORN RELAY
Page 18 Teledyne Analytical Instruments 9070 Oxygen Analyzer
