Emerson Mobrey MCU900 Series, Safety Instructions

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IP2030/SI
Page 2
GB Instructions specific to hazardous area installations
Model numbers covered: MCU*****-A*** ("*" indicates options in construction, function and materials). The following instructions
apply to equipment covered by certificates numbered
BAS00ATEX7064 , BAS01ATEX7225X , and IECEx SIR 06.0090X :
1.
The MCU900 control unit may be connected to a transmitter located in a hazardous area. The MCU control unit must
not itself be located in a hazardous area.
2.
General
a. Do not mount the MCU on a structure that is subject to vibration, or in a position where damage may be caused
by impact, thermal stress or liquid ingress.
b. The fuse must only be replaced with the type specified.
c. It is the responsibility of the user to ensure:
(
c.1. ) the voltage and current limits for this equipment are not exceeded.
d. If the equipment is likely to come into contact with aggressive substances, it is the responsibility of the user to
take suitable precautions that prevent it from being adversely affected, thus ensuring that the type of protection is
not compromised.
Aggressive Substances – e.g. acidic liquids or gases that may attack metals or solvents that may affect polymeric
materials.
Suitable Precautions – e.g. regular checks as part of routine inspections or establishing from the material’s data
sheet that it is resistant to specific chemicals.
e. The user should not repair this equipment.
3. Wiring instructions
a. Terminal 30 of the MCU Control Unit must be connected to an Intrinsically Safe earth.
b. The MCU must not be connected to a supply exceeding 250V r.m.s. or dc, or to apparatus containing a source of
voltage exceeding 250V r.m.s. or dc.
c. The Intrinsically Safe outputs of the MCU Control Unit may be connected to certified equipment used in a hazardous
area requiring Equipment Protection Level Ga or Da (category 1) equipment, with flammable gases and vapours
groups IIC, IIB, and IIA, and flammable dusts groups IIIC, IIIB, and IIIA. No additional I.S. barrier is required.
d. If the circuit connected to Terminal 1 and Terminal 2 does not satisfy EN60079-11 clause 6.4.12 (Isolation of circuits
from earth or frame) then equipotential earthing to the MCU900 intrinsically safe earth shall be provided. An
equipotential earthing example is a cable with a cross-sectional area greater than 4 mm
2
and a resistance of 1 Ohm.
4. Technical Data:
Coding: II (1) GD
[Ex ia] IIC (-40

C

Ta

55

C)
[Ex ia Da] IIIC (-40

C

Ta

55

C)
a.
Terminal 1 (24V) with respect to terminal 2 (I
in
)
Terminal 1 (24V) with respect to terminal 3 (Earth)
Terminal 2 (I
in
) with respect to terminal 3 (Earth)
ATEX Ui = 0, Uo = 28 V, Io = 120 mA, Po = 0.82 W,
Li = 0.2 mH, Ci = 0.6 nF Ui = 30 V, Ii = 120 mA, Li = 0.1 mH, Ci = 0.6 nF,
Uo = 6.51 V (Cap. charging only), Io = 0, Po = 0
IECEx Ui = 0, Uo = 27.3 V, Io = 96.9 mA, Po = 0.66 W,
Li = 0.2 mH, Ci = 0.6 nF Ui = 30 V, Ii = 120 mA, Li = 0.1 mH, Ci = 0.6 nF,
Uo = 6.51 V (Cap. charging only), Io = 0, Po = 0
b.
Group Capacitance Inductance or L/R Ratio
IIC
0.082µF *
1.2mH
42 µH/

IIB 0.65µF 10.9mH 172 µH/

IIA 2.15µF 21.9mH
346 µH/

* 0.082µF of which total Ci of the hazardous area apparatus connected must not exceed 0.020µF.