Equflow 6010BCPM Pulse Input Batch Controller Instruction Manual
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Relay Operation Details
Overview
The relays of the controller can serve three roles, as batch control relays for single or multi-stage
batching, as rate, or grand total alarm, or as a sampling relay based on grand total or rate alarm.
These capabilities include front panel alarm status LEDs and 2 internal relays.
The relays used for batch control (total) are activated when the batching process starts, and deactivate
when the batch total is reached, minus any preclose amount programmed for batch (total) relays after the
first.
For an example of batch control operation, see Batch Control Operation Example on page 17.
Typical applications for alarms are low and high flow alarms or grand total limit alarms. Note that rate
alarms are only enabled during a batching process, and deactivate when the processes is stopped.
The relays can also be set for sampling, where the relay will activate for a specific amount of time after a
certain grand total has been reached (ie: 2 second sample relay activation every 100 gallons batched).
There are three basic ways the relays can be used:
1. Batch Control (Total)
2. High or Low Alarms for Rate or Grand Total
3. Sampling (Based on Grand Total and Sample Time)
Relays Initialization
Batch control (total) relays will activate when the start function is enabled, such as when the START
button is pressed. Rate alarm relays will enable and initialize to their programmed states when the batch
process is started. Grand total alarm relays will initialize to their programmed state at controller power-up.
Fail-Safe Operation
The following table indicates
how alarm relays behave
based on the fail-safe
selection for each relay:
Note: NO = Normally Open,
NC = Normally Closed. This
refers to the condition of the
relay contacts when the power to the controller is off.
Front Panel LEDs
The LEDs on the front panel provide status indication for the following:
The controller is supplied with four alarm points that include front panel LEDs to
indicate alarm conditions. This standard feature is particularly useful for alarm
applications that require visual-only indication. The LEDs are controlled by the set
and reset points programmed by the user. When the display reaches a set point for a high or low alarm,
the corresponding alarm LED will turn on. When the display returns to the reset point the LED will go off.
Note that rate alarms are only enabled during a batching process, and deactivate when the processes are
stopped.
Latching relays, or relays with manual reset, are not recommended when using this controller for batch
control, as the manual reset will not be acknowledged during a batch process, when the rate alarms are
active. For information on latching and manual reset alarms, see the 6010FCPM instruction manual
available at www.equflow.com.
Fail-Safe
Selection
De-Energized State
Energized State
Power Failure
NO
NC
NO
NC
Off
Open
Closed
Closed
Open
Relays in de-
energized state
On
Closed
Open
Open
Closed
Relays in
energized state
LED
Status
1
Alarm 1
2
Alarm 2
