I-GARD DSP-OHMNI Instruction Manual
6
DSP (Outline Dimensions). Care should be taken not to over tighten the 8-32 nuts used to retain the
DSP-DM
It will be necessary to provide a reliable power source (which is not interrupted by operation of the DSP
output contacts) for control power. The supply should be 100-240 V AC/DC. The control supply must be
fused by 1 Ampere fuses as shown in Fig.
4.1 a
(Connection Diagram). Ideally the alarm, warning bell should
be connected to a separate control supply from the DSP (see para. 8.3.1).
4
WIRING
No
.
14 or No
.
16 switchboard wire is used for all current sensor, control and DDR2 connections, which need
not be shielded. 4-wire shielded cable should be used for the serial communications, however. A typical
wiring schematic is shown in Figure 4.1a.
Sensor wiring is not generally limited by length and may be up to a kilometer without degradation of
performance, since the sensor is a current source. Sensor wiring should be run in separate conduit from
Power wiring. The recommended sensor wiring connections are shown in Figure 4.2. Two wires should
be run from each sensor X1 and X2 as indicated to prevent cross coupling between Modules. If existing
wiring does not allow this connection because of common connection at X2 as has been common in some
installations, then the G terminals of the DSP-DFM modules should be connected as shown in Figure 4.3.
Ribbon cables are available in different lengths as shown in Table 3.2. For other lengths contact
I-Gard. The DRC-cable from the DSP-DM to the DSP-DPS, apart from being different in length, also differs
in the orientation of the connector. This allows the cable to be run easily from the DSP-DM towards the
DSP-DPS power supply. The RC-cables are used for Module to Module connections and are short in
length. Note the orientation of the plug as marked on the DSP-DM display module. If a second row of
modules is installed on another DIN rail
,
the last module on the right can be connected to the last module
on the right on the second row using the RC-30 cable. Either slot can be used on the DSP-DFM feeder
modules for connection.
