Applications: These terminal blocks have been developed to meet the specific needs of connections that must withstand very high temperatures, up to 500°C (930°F) permanently and 750°C (1290°F) peak. They also ensure the continuity of the connection in case of fire up to 900°C (1650°F) (Their subsequent replacement is then necessary). They are particularly intended for road tunnels, public transport tunnels (trains, subways), boat and submarine parts that must withstand a fire, but also for furnace connections when the ambient temperature is permanently very high. Because of their construction, they are non-flammable and resistant to moisture. Although standards IEC (EN) 60998-1 and IEC (EN) 60998-2 have not provided for the special temperature holding conditions of these terminal blocks, their construction meets their specifications (where applicable), for a maximum voltage of 750V.
At 700°C, in 230V, the leakage current to earth is about 0.1milliampere; The IEC 60331-21 and IEC 60331-11 standards for fire resistance of cables require a maximum leakage current of 2A at 850°C. It is reached only around 900 ° C in these terminals, for a voltage of 230V
Not protected against accidental electrical contact, they must be installed inside protection boxes
Typical insulation resistance between two terminals:
at 100°C (212°F): 1500 MΩ
at 500°C (900°F): 1000 MΩ
at 700°C (1290°F): 650 MΩ
at 900°C (1650°F): 10 MΩ
Dielectric strength: Higher than 6000V at 20°C
Screws: M4x8, 304 stainless steel, with spring washer against loosening at high temperature. Recommended torque 13~20 DaN.cm
Two possible types of screw heads: Phillips or slot upon DIN84
Terminals: 304 Stainless steel
Saddles: 304 Stainless Steel, with or without safety tab against wire shearing
Max wire gauges (per terminal, wires inserted between saddle and connector plate):
– 1 single flexible conductor in 10 mm² (AWG8) or 6mm² (AWG10) whose strands must then be divided into two on either side of the screw.
– One or two flexible conductors in 4mm² (AWG 12), 2.5mm² (AWG14), 1.5mm² (AWG16)
– One or two solid conductors in 6mm² (AWG10), 4mm² (AWG 12), 2.5mm² (AWG14), 1.5mm² (AWG16).
Current carrying capacity: 32A per terminal
Maximum operating voltage: 750V, in pollution class 3. (Pollution class 3 defines micro environmental conditions causing conductive pollution, or when a non-conductive pollution can become it in case of condensation).
Insulation distances: Greater than 10 mm between mounting face and terminals, between terminals, and 6.4mm between two connection blocks mounted side by side.
Live parts: Not protected against accidental electrical contact
Important note: These terminal blocks must imperatively be fixed in order to prevent their movement for any reason in the box in which they are mounted, and consequently put them in a position where the insulation distances are no longer respected.
Maximum ambient temperature:
– Permanent: 500°C (900°F)
– In peak short duration: 700°C (1292°F)
– Fire: 900°C (1650°F) for two hours (Afterwards equipment must be replaced, but it retains its main characteristics during the fire)
The temperature resistance values of the stainless-steel terminals were validated by wire pull tests according to EN 60998, performed after 48H at 500°C (930°F) and 90 minutes at 700°C (1290°F).
Partially applicable standards: (IEC) EN 60998-1; (IEC) EN 60998-2-1
Caution: Special care must be taken to avoid electric shock. These terminal blocks are not usable in places accessible without tools. They must be mounted in protective boxes. Respect the distances in the air of at least 6mm between the parts under tension and the walls of the protective case. Other rules may apply according to local safety regulations.
Options: These terminal blocks can be made with brass or nickel terminals and saddles (MOQ apply and references on request). In these two configurations, the maximum permissible intensity per terminal rises from 37A to 53A, and the temperature resistance conditions are modified as follows:
|Material||Permanent temperature||Peak Temperature||Fire conditions Temperature|
|Brass||230°C (450°F)||450°C (840°F)||Not resistant|
|Nickel||500°C (930°F)||700°C (1290°F)||120 min at 950°C (1740°F)|