Dwyer MTL5045 User Manual
Page 36
6.35
MTL5991 24V dc power supply
The MTL5991 provides a convenient source of power for MTL5000
Series units in locations where a dc supply is not readily available. The
2A capability at 24V dc is sufficient to drive at least fifteen (15)
MTL5000 Series modules, or more in appropriate combinations (see
table 6.16), and the wide mains power supply range makes this unit
universally applicable.
Table 6.16
Note:The maximum current drawn from the load unit is taken at 24V.
The maximum current drawn from the MTL5991 was taken to be 1.6A
6.35.1
Wiring connections
See figure 6.80 for wiring connections.
32
INM5000-6 Jul 2010
Current
MTL5000 unit
Drawn mA
Maximum
(Vs=24V)
number of units
MTL5011B
35
46
MTL5012
30
53
MTL5014
45
36
MTL5015
44
36
MTL5017
50
32
MTL5018
60
27
MTL5023
100
16
MTL5024
100
16
MTL5031
80
20
MTL5032
65
25
MTL5040
95
17
MTL5041
70
23
MTL5042
75
21
MTL5044
110
15
MTL5045
50
32
MTL5046
65
25
MTL5048
40
35
MTL5049
65
25
MTL5051
90
18
MTL5074
68
24
MTL5081
20
80
MTL5082
55
29
MTL5113P
70
23
MTL5314
85
19
MTL5344
122
13
MTL5349
67
24
WARNING
Segregation between hazardous- and safe-area wiring
must always be maintained
4
5
6
7
8
+
1
2
3
Figure 6.80: MTL5991 wiring diagram and connections
Terminal
Function
1
AC Line
2
Earth
3
AC neutral
4
+24V
5
+24V
6
OV
7
OV
8
Do not use
Safe area
6.35.2
Testing
Using the terminal assignments shown in figure 6.81, make the following
tests and checks.
1. Connect a supply voltage of between 85V and 264V ac to the
live and neutral terminals. Check that the voltage measured
across these terminals is within the range 85V to 264V ac.
2
With no load connected to the unit's output, measure, in turn, the
voltage between terminals 4 and 6 then 5 and 7. Check that the
measurements are in the range 23.64V to 24.36V.
3
Connect to the output, a load that draws up to 2A from a supply
voltage between 105V and 264V ac, and draws 1.7A when the
supply voltage is less than 105V ac. Measure, in turn, the voltage
across terminals 4 and 6 and 5 and 7. Check that these
measurements are in the range 23.64V to 24.36V with a ripple
not greater than 100mV.
6.36
MTL5995 fieldbus power supply for
31.25kbit/s fieldbuses
The MTL5995 is a general purpose power supply unit designed for use
in 31.25kbit/s (H1) fieldbus systems. The MTL5995 complies with the
requirements of Fieldbus Foundation™ power supply Type 131 (non-IS
supply intended for feeding an IS barrier).).
To allow adequate heat dissipation under all likely thermal conditions, it
is recommended that MTL5995s are installed on DIN rail with a 10mm
space between adjacent units. MTL MS010 10mm DIN-rail module
spacers are available for this purpose (see section 4.2.1).
To comply with fieldbus standards, each bus must be terminated at both
ends. MTL's FBT1-IS or FCS-MBT fieldbus terminators (see section 6.37)
can be supplied for this purpose or, for installations in which the
MTL5995 is located at one end of the fieldbus trunk, it includes an
internal terminator which is enabled by a yellow switch (B) located on
the base of the unit (see figure 6.82). A second, red switch (A) in the
base of the unit should be kept in the normal mode position.
(For network and termination criteria, see applicable fieldbus standards
and specification
IEC 61158-2, ISA-S50.02 for 31.25kbit/s fieldbus
systems, Foundation™ Fieldbus 31.25kbit/s Physical Layer Profile
Specification FF-816 and MTL's Application Brief AB001.)
4
5
6
L
E
N
7
8
+
Figure 6.81: Terminal assignments for MTL5991
A
B
2
1
NORMAL MODE SW1
TERMINATOR OUT SW2
NOT USED
Red
Yellow
TERMINATOR IN
Label face
Base of unit
Figure 6.82: Functions of switches on the base of an MTL5995