To Fit Irmax To An Auxiliary Junction Box; Cabling Requirement - Crowcon IRmax Instructions D'installation, D'utilisation Et De Maintenance

2. Installation

2.4.1 To fit IRmax to an auxiliary junction box:

a. Carefully remove the outer section of the spigot gland (item 8 in Diagram 3 on
page 5).
b. Screw the narrow end of the spigot gland into the auxiliary junction box.
c. Raise the IRmax to the auxiliary junction box and pass the wires through the
assembly and into the auxiliary junction box. Secure the IRmax by screwing the
collar tightly to the cable gland. Tighten grub screw.
d. The main body of the IRmax can be swivelled horizontally at any angle, provided
it is mechanically secure, does not interfere with other equipment and is
accessible for maintenance.
e. Refer to Section 2.6 for instructions on wiring. See also Diagram 4 on page 7.

2.5 Cabling requirement

Cabling to IRmax must be in accordance with the recognised standards of the appropriate
authority in the country concerned and meet the electrical requirements of the IRmax.
Crowcon recommends the use of steel wire armoured (SWA) cable and suitable explosion
proof glands must be used. Alternative cabling techniques, such as steel conduit, may be
acceptable provided appropriate standards are met.
The maximum recommended cable length is 3.4 km (see Table 1).
IRmax requires a dc supply of 12-30Vdc. Ensure there is a minimum of 12V at the IRmax
from the control panel, taking into account the voltage drop due to cable resistance at a
peak current of 0.1A.
2
A 1.5mm cable will typically allow cable runs up to 3.0km. Table 1 below shows the
maximum cable distances for typical cable parameters.
C.S.A.
mm 2
1.0
1.5
2.5
Table 1: Maximum cable distances for typical cables
Resistance
(Ohms per km)
18.4
13.0
11.5
10
Max. Distance
>20 V
(km)
2.2
3.0
3.4
Max. Distance
18 to 20 V
(km)
1.6
2.3
2.6
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