Operator Manual

748223-K June 2002

Model 7003M

c.Relay Contacts

Relay contacts are listed in Table 3-18 below:

RELAY POS

TERMINAL LOCATIONS

ALARM1

ALARM2

 

NO (Normally open)

TB3-3

TB3-6

NC (Normally closed)

TB3-2

TB3-5

COM (Common)

TB3-1

TB3-4

Relay positions are with power removed.

Table 3-18. Alarm Relay Contact Positions/Terminal Locations

d. Fail Safe Operation

g. Setting Alarm and ON/OFF-Controller

 

Relays

The relays are setup to operated in "Fail Safe" configuration. In this configuration the relay coils are powered when the unit is NOT in an alarm condition. When an alarm condition occurs, power is removed from the relay coils.

If a power failure occurs, power will be removed from the relays and an alarm condition will be indicated to the device connected to the relays.

e.Relay Reset Upon Fatal Error

If a fatal error is detected, the unit will attempt to reset itself which will make both relays go into alarm mode. If the microprocessor is able to continue its operation, the relays will then be reset to their normal operating position.

f.Pressure Effects on Alarms

If the sample pressure changes, the partial pressure of oxygen, and thus the reading, will change and the alarm relays will not actuate at the same oxygen levels as they were set when the interment was last calibrated. See Section 5-2a on page 5-1 for a more detailed description of pressure effects.

Wherever "Alarm" is referred to in this section, the term "ON/OFF-Controller" can be substituted, unless specifically called out. Also, any reference to A1 or Alarm 1 also applies to Alarm 2, and to ON/OFF- Controllers 1 and 2.

h.Setting Alarm Setpoints

This procedure can be used to:

•Verify alarm relay setpoints

•Change setpoints

•Enable alarms

•Disable alarms

Perform the following procedure for each Alarm setpoint, as required. Figure 3-6 illustrates how relays are energized and de-energized in High and Low Alarm configurations.

3-18 Operation

Rosemount Analytical Inc. A Division of Emerson Process Management