Industrial Environment
DC-DC Converters <40 Watt
IMS 7 Series
Edition 5/9.99
13/15
MELCHER
The Power Partners.
Protection Degree
The protection degree of the DC-DC converters is IP 30.
Safety of operator accessible output circuit
If the output circuit of a DC-DC converter is operator acces-
sible, it shall be an SELV circuit according to IEC/EN 60950
related safety standards
The insulation concept table below shows some possible
installation configurations, compliance with which causes
the output circuit of the DC-DC converter to be an SELV cir-
cuit according to IEC/EN 60950 up to a configured output
voltage (sum of nominal voltages if in series or +/– configu-
ration) of 42 V.
However, it is the sole responsibility of the installer to en-
sure the compliance with the relevant and applicable safety
regulations. More information is given in:
Technical Infor-
mation: Safety.
Safety and Installation Instructions
Installation Instruction
Installation of the DC-DC converters must strictly follow the
national safety regulations in compliance with the enclo-
sure, mounting, creepage, clearance, casualty, markings
and segregation requirements of the end-use application.
Connection to the system shall be made via a printed circuit
board according to:
Mechanical Data.
The units should be connected to a secondary circuit.
Check for hazardous voltages before altering any connec-
tions.
Do not open the module.
Ensure that a unit failure (e.g. by an internal short-circuit)
does not result in a hazardous condition. See also:
Safety
of operator accessible output circuit.
Input Fuse
To prevent excessive current flowing through the input sup-
ply line in case of a short-circuit across the converter input
an external fuse should be installed in a non earthed input
supply line. We recommend a fast acting fuse F2A for
24 IMS 7 types and F1A for 48 IMS 7 types.
Cleaning Agents
In order to avoid possible damage, any penetration of
cleaning fluids has to be prevented, since the power sup-
plies are not hermetically sealed.
Standards and approvals
All DC-DC converters are UL recognized according to
UL 1950, UL recognized for Canada to CAN/CSA C22.2
No. 950-95 and LGA approved to IEC/EN 60950 standards.
The units have been evaluated for:
Building in
Supplementary insulation input to output, based on their
maximum input voltage
The use in a pollution degree 2 environment
Connecting the input to a secondary circuit which is sub-
ject to a maximum transient rating of 1500 V
The DC-DC converters are subject to manufacturing sur-
veillance in accordance with the above mentioned UL,
CSA, EN and ISO 9001 standards.
Isolation
The electric strength test is performed as factory test in ac-
cordance with IEC/EN 60950 and UL 1950 and should not
be repeated in the field. Melcher will not honour any guar-
antee claims resulting from electric strength field tests.
Table 12: Electric strength test voltages, clearance and
creepage distances
Characteristic
I/O
O/O
Unit
Electric strength
1.2
0.1
kVrms
test voltage 1 s
1.5
0.15
kV DC
Coupling capacitance
≈1.2
-
nF
Isulation resistance
>100
-
M
at 500 V DC
Partial discharge
Consult
-
kV
extinction voltage
factory
Fig. 23
Pin allocation standard pinout
1
2
3
4
5
10012
Fig. 24
Pin allocation C pinout, bottom view
Table 14: Pin allocation for C-pinout (option C)
Pin
Single output units
Dual output units
1
Vi+
2Vi–
Vi–
3Vo+
Vo+
4
no pin
Go
5Vo–
Vo–
Table 13: Pin allocation, standard pinout
Pin
Single output units
Double output units
1
Vi+
2Vi–
Vi–
3i
i
4
n.c.
R (Trim)
10
Vo–
Vo1–
11
Vo+
Vo1+
12
Vo–
Vo2–
13
R
Vo2+
14
n.c.
Bottom view
1
4
10
14
10011
2
3
11
12
13