Bosch Appliances Smoke Alarm D2071A User Manual

11

Bosch | 09/04 | 74-06200-000-F

•

If the time specified in the retard time accumulates in
one or more successive alarm activations, the
D2071A transmits an Alarm Zone 1 Report and
activates the Alarm Relay.

•

The retard timer resets to zero only when the circuit
remains in a non-alarm condition (restored or
trouble) for the time entered in reset time.

•

When the alarm initiating circuit is normal for the
time specified in reset time, the D2071A sends a
Restoral Zone 1 Report.

Generally, the reset time is set to approximately half the
retard time. For example, if retard time is set at 15 sec,
reset time is set at 7 or 8 sec.

2.2.3

Wiring

Stand-Alone Applications

Connect the normally-open (NO) contacts of each
waterflow switch (a maximum of five) or mechanically
activated initiating device to the alarm initiating circuit
in parallel as shown in Figure 2 on page 8.

Slave Communicator Applications

1.

Connect the alarm initiating circuit to an alarm
indicator output (NO, dry closure) on the FACP
(Figure 3 on page 9).

2. Connect Terminals 6 and 7 to the common (C)

contact. Connect Terminals 8 and 9 to the NO
contact.

3. Program the retard and reset times to 0 sec when

connecting the alarm initiating circuit to an existing
FACP.

2.3

Zones 2 and 3 (Supervisory Circuits)

 

Use Terminals 10, 11, and 12 for supervisory 
circuit connections. 

 

Zones 2 and 3 are Class “B” circuits that monitor
sprinkler supervision devices such as valve tampers
(maximum of 20 per circuit) in stand-alone applications.
In slave communicator applications, these circuits
monitor the trouble outputs of an associated FACP.

1.

Wire Class “B” circuits in Modes 1, 2, or 3.
Class “B” Mode determines the mode for Zones 2
and 3.

2. Wire both circuits for the same mode configuration.

3. Connect dry contact devices to the supervisory

circuits in series (normally-closed [NC]) or in
parallel (NO).

4. As necessary, install a 1.8 k

Ω

 EOL resistor at the

end of the Class “B” circuits.

2.3.1

Mode 1

In Mode 1 (Figure 4 ) the loops are configured for NC
devices only, no EOL resistor is used. The loops are not
supervised for troubles. This mode is not acceptable for
the stand-alone applications.

The Mode 1 status conditions are:

Normal: 0.0 VDC to 1.5 VDC

Alarm (Open): 1.8 VDC to 13.0 VDC

2.3.2

Mode 2

Mode 2 (Figure 5) uses a 1.8 k

Ω

 EOL resistor across

each NC device in the series loops. This mode is
acceptable for NFPA 72 central station and remote
station stand-alone applications only when an NC valve
tamper device must be used and only upon approval of
the AHJ.

The Mode 2 status conditions are:

Normal: 0.0 VDC to 1.5 VDC

Alarm (Resistance): 1.8 VDC to 9.0 VDC

Trouble (Break): 9.3 VDC to 13.0 VDC

A single off-normal device puts the loops into alarm. A
broken circuit or multiple off-normal devices put the
loops into trouble, unless the loop was previously in
alarm.

Figure 5:

Mode 2 Class “B” Wiring

Ω

Figure 4:

Mode 1 Class “B” Wiring

D2071A  | Operations & Installation Guide | 2.0    Installation