Setting Up The Interlock Relay (Force On) Feature - Ametek DDMC Instruction Manual

DDMC Analog Input Process Meter / Controller
The following graphics provide a visual representation
of a typical pump alternation application with high and
low alarm monitoring:
1. Relay #4 turns the main pump on at 6000 gallons
and turns it off at 1000 gallons.
2. With the Pump Alternation feature activated, the
next time the level reaches 6000 gallons, relay #3
transfers and starts the backup pump.
3. If the backup pump is not able to keep up, and
the level reaches 7000 gallons, relay #4 transfers
and starts the main pump as well.
4. Relay #2 trips the High Level Alarm at 7500
gallons and resets at 6900 gallons.
5. Relay #1 trips the Low Level Alarm at 495 gallons
and resets at 750 gallons.
Setting Up the Interlock Relay (Force
On) Feature
Relays 1-4 can be set up as interlock relays. To set
up the relays for the interlock feature:
1. Access the Setup – Relay – Action menu and set
the action to off.
2. In the Advanced features – User menu program
any of the digital inputs to Force On any of the
internal relays (1-4).
3. Connect a switch or dry contact between the +5V
terminal and the corresponding digital input (dI-1
to dI-4) terminal.
SW2
SW1
1 2 3 4
+5 I1 I2 I3
DI 1-4
5 VDC
Interlock Relay Operation Example
Relays 1 & 2 are configured to energize (their front
panel LEDs are steady on) when SW1 & SW2
switches (above) are closed. If the contacts to these
digital inputs are opened, the corresponding front
panel LEDs flash indicating this condition. The
processes being controlled by the interlock relay will
stop, and will re-start only after the interlock relay is
re-activated by the digital inputs (switches).
Note: If multiple digital inputs are assigned to the
same relay, then the corresponding logic is (AND) –
i.e. both switches must be closed to activate the relay.
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Instruction Manual
5 6 7 8 9 10
I4 O1 O2 O3 O4 G
DO 1-4
GND