44
9M02-8978-A002-EN
Version 14
Safe-E-
Stop™
User Guide
8.8.4 MSD Connections
Before installing the MSD, prepare an electrical wiring diagram that defines all electrical interface
connections between the system and the equipment being controlled.
Cattron also advises you to first read the following topics of discussion at the same time; you should
locate and refer to the example mainline drawing provided.
Do not exceed the relay rating, see Appendix V. When connected to contactors, protect these relay
contacts with suitably rated transient suppression devices to maximize contact life expectancy and
prevent whiskers growing.
Overload protection <=8A for the relays and 1A for the power supply and means to isolate the MSD from
power when required should be in place. The Supply voltage is 24Vdc nominal (9-36Vdc), maximum
current is 1A, nominal current at 24V is 250mA. The MSD is fitted with a protective fuse next to the DC
input terminal (Cattron part number PRT-0001852) rated at
1A. An optional wide range (85-264VAC 47-
63Hz 1A) power supply is available from Cattron.
Care should also be taken to provide suitably rated overload protection and isolation device when using
the external power supply, this should also have a 1A overload protective device.
The Safety inputs are rated at 24Vdc +- 4Vdc, Omni-directional (non-polarized).
8.8.5 MSD Terminals
The MSD is fitted with spring clamp terminals to ensure reliable connections are continuously maintained.
These terminals require the use of a size 3 screwdriver to open the clamp for release, (CAUTION, do not
press the release clamp too hard or it may damage the terminal); the ferrules are simply pushed in for
insertion.
The use of ferrules to eliminate any possibility of wire strands shorting to adjacent terminals and to aid
insertion into the spring clamps is required.
8.8.5.1 Terminal and Wire Specifications
NB: Wire sizes less than 0.459 mm
2
, 24AWG are not allowed and the temperature rating must be
approved for greater than 80 Celsius, for electrical safety certification compliance.
*For voltages greater than 24Vdc wire sizes of 18AWG (0.82mm
2
) minimum are recommended, but in all
cases the wiring must be correctly rated for its intended service,
Wire gauge : https://en.wikipedia.org/wiki/American_wire_gauge
Insulation:
http://iq.ul.com/awm/stylepage.aspx?style=1015
Table 18: Terminals Maximum Wire Capacity
INPUTS AND
OUTPUTS
POWER
IN
TEMPERATURE
RATING
USE OF
FERRULES
Size mm
2
0.459* to 1.5
0.459* to 2.5
>80C (176F)
Required
Size AWG
24* to 16
24* to 12
>80C (176F)
Required
