DO
CT
-194
6C
2018
-07
32
2903
Trip Amplifier 2/209
Hardware description
12
EN
3.2
Cabinet design and h
eat dissipation
Electronic devices will dissipate some of the energy applied to them in the form of heat.
The resulting cabinet temperature must not impair the device function. Therefore the
cabinets should be designed not to exceed the maximum permissible ambient
temperatures as given in the section "Technical data". The following table is based on
an over-temperature of 25 K.
The devices have been designed for 60 °C ambient. Further assuming that the control
room temperature does not exceed 40 °C, the permissible power dissipation in the
cabinet can be given as follows:
1. unforced draught convection 400 W
2. draught convection using vents and filters 800 W
3. draught convection using vents without filters 1600 W
4. unforced natural convection 160 W
5. forced convection ventilators per rack 320 W
6. forced convection using heat exchangers plus forced convection inside and out
1500 W
The number of devices per cabinet can then be computed as follows:
For mixed installations the individual power dissipation of devices can be used to
compute the total power loss to compare with the permissible values.
3.3
Connections
Devices are electrically connected using a male and female connector to DIN 41612,
type F. Connections see section "Technical data". The male connector is mounted on
the printed circuit board while the female connector is fitted at the back of the rack.
External connections are normally soldered to the connectors. The solder points are
covered by a heat shrunk sheath e. g. Drakavita Ray Quality H, manufacturer: Deutsche
Schrumpfschlauch Gesellschaft. Other wiring techniques are also acceptable (wire-
wrap, termipoint, crimp snap-in etc.).
For all device types the rules and regulations for the installation of electrical equipment
and wiring (e. g. VDE 0100) of the user country must be observed.
Power and measuring cables have to be kept separate.
V
Z = –––
G
Z = number of devices per cabinet
V = permissible power dissipation
G = power per device
Attention