3.1.4
Installing the transmitter in underground mines
susceptible to firedamp
Install a safety barrier or a power supply with the appropriate
explosion protection approval (category M1) between the
transmitter and the control unit.
Only safety barriers or power supplies with the following
characteristics may be used: U
700 mW.
Take care that the maximum permissible capacitance and inductance
of connections to the safety barrier or power supply are not exceeded,
also taking the cable into account. The safety-related input parameters
of the transmitter are:
Polytron 3000: Ci = 0 nF, Li = 50 μH
Polytron 7000: Ci = 5 nF, Li = 50 μH
3.1.5
Installing the transmitter in areas subject to explosion
hazards of zone 0 or zone 1
Install a safety barrier with the appropriate explosion protection
approval (category 1, 2) between the transmitter and the control unit.
Only safety barriers with the following characteristics may be used: U
) 30 V, I
) 0.3 A, P
(V
(I
oc
o
sc
o
Take care that the maximum permissible capacitance and inductance
of connections to the safety barrier are not exceeded, also taking the
cable into account. The safety-related input parameters of the
transmitter are:
Polytron 3000: Ci = 0 nF, Li = 50 μH
Polytron 7000: Ci = 5 nF, Li = 50 μH
Connect the shielding to potential equalization (equipotential bonding)
or 0 V (Ex-i).
Dräger Docking Station for Polytron 3000/7000
) 30 V, I
) 0.3 A, P
(V
(I
O
OC
O
SC
700 mW.
Explosion-Hazard area, zone 0, 1 or Div. 1
O
o
Ex i
Safety barrier
PA
Non-explosion-hazard area
Installing electrical connections
+24 V
4 to 20 mA
+
4 ... 20 mA
0 V
Control Unit
Earth point
00423760_4_en.eps
+
–
15