Hach-Lange High Output Airblast System (HOAB) - Manual (Page 10)

• Be near the installed equipment
• Meet all local electrical codes
• Be identified as the disconnect device for the instrument
Refer to Figure 5 on page 9 for an example of a recommended local disconnect installation.
A conduit bonding to the instrument enclosure does not automatically supply a ground. Make sure
that the electrical metal conduit is grounded.
To prevent damage to enclosure seals, equipment attached to vertical or horizontal pipes must use
waterproof flexible conduit or flexible cable rated for the location.
Wiring guidelines
Insert wires into connectors until the insulation is seated against the connector with no bare wire
visible. Pull gently on each wire after installation to make sure it is held securely.
Use NEMA/IP-rated, conduit hubs or strain relief fittings to keep the environmental rating.
The controller wiring uses 22 to 18 AWG wire (0.32 to 0.82 mm²). Do not use wire size less than
22 AWG (0.32 mm²).
Install the sc controller voltage barrier when the 24 Vrms control wiring of the instrument is
connected. Refer to
Install the voltage barrier on page 14.
Do not use both high and low voltage in the sc controller. When the sc controller is used with this
instrument, use only low voltage (less than 30 Vrms or 60 VDC) in the sc controller wiring
compartment, behind the voltage barrier.
Refer to the controller manual for relay connection details and to
Figure 6 on page 11 and Figure 7
on page 12 for connection details. Refer to the instructions in the controller manual to install all the
remaining barriers and covers.
Connect the wiring to the controller
D A N G E R
Electrocution hazard. Remove all power from the instrument and relay connections before this
maintenance task is started.
1. Make sure that power to the controller is turned off.
2. Open the controller. Refer to
Install the voltage barrier on page 14.
3. Connect the wire from the instrument COM (common) relay to the controller COM relay.
4. Connect the wire from the instrument N/O (normally open) relay to the controller N/O relay.
5. Make the remaining wiring connections. Refer to
Connect the wiring to the instrument
on page 10.
6. Make sure that the power wiring is on the right side of the standoff.
7. Install the controller voltage barrier. Refer to
Install the voltage barrier on page 14.
8. Close the enclosure cover. Tighten the cover screws to seal the enclosure. The enclosure cover
must be installed to keep the enclosure environmental ratings.
Connect the wiring to the instrument
D A N G E R
Electrocution hazard. Always remove power to the instrument before making electrical connections.
Refer to Table 1 , Figure 6 , Figure 7 and Figure 8 .
1. Remove the three screws from the clear cover and remove the cover.
2. Connect the wire from the controller COM (common) relay to the instrument COM relay.
3. Connect the wire from the controller N/O (normally open) relay to the instrument N/O relay.
10 English