User's Manual
MS3725
Slim Plug-In High/Low Signal Selector with Isolated Single/Dual Output
Rev. 1.60
2
On Wiring:
Connections to the instrument should be made to the terminal
block. For assignment of the terminals, refer to section 6. The
recommended screwing torque is 0.8 to 1.0 Nm.
For lead wires, use a highly flexible stranded conductor. The
recommended nominal cross-section of the lead wire conductor
is 0.5 to 2.0 mm
2
.
The connection of the lead wire to the terminal block should be
made with the insulated crimp terminal attached to the end of the
wire. Without the insulation, short circuit or electric shock may
occur. The recommended thickness of the crimp terminal is 0.7
to 1.0 mm.
Note that only up to two (2) crimp terminals can be connected to
one (1) terminal screw. In this case, the thickness of the crimp
terminal should be not greater than 0.8 mm.
φ3.7
6.8
m
ax
.
3.4 max.
4.6 min.
To Avoid Erroneous Measurement:
In order to reduce the influence of noise, the input/output wire
and power supply wire should not be used in a same bundle or
same conduit. They should be installed separately with a
minimum distance of 200 mm.
Avoid wiring the signal lines in the vicinity of equipment
generating magnetic fields or electromagnetic waves, such as
electric motors and large-scale transformers. If inevitable,
anti-noise measures such as employment of shielded wires are
indispensable.
At least 30 minutes of warm-up is required prior to operation.
Any sensor or equipment to be connected to the instrument
should be selected in consideration of the input/output
impedance of the same. (For detailed specifications, refer to
section 4 or the relevant product specification sheet that can be
downloaded from our website at https://www.mtt.co.jp.)
Special Notes for CE Marking:
The instrument is designed and manufactured to conform to the
following EMC and Low Voltage Directives:
EMC Directive (2014/30/EU)
- Standard conformity: EN61326-1:2013 Class A
Low Voltage Directive (2014/35/EU)
- Standard conformity: IEC61010-1
EN61010-1:2010/A1:2019
- Overvoltage Category: II
- Pollution Degree: 2
The instrument must be installed in a control panel.
The instrument maintains basic insulation between input and
output, and between output and FG. Prior to installation, check
that the insulation class of the instrument satisfies your system
requirements.
When the instrument is installed in a control panel, the measures
to be taken for CE marking conformity may vary with the type of
devices connected, wiring to the instrument or structure of the
control panel. Therefore, you should check that the control panel
as an overall system conforms to the CE marking regulations.
4. About the Product
The MS3725 selects the higher or lower of two DC input signals and
converts it into isolated DC output.
Features:
Pin and socket contacts are gold-plated (0.2
μ
m) to ensure high
reliability and long-term stability.
High dielectric strength of 2,000 VAC between input, [output 1,
output 2], power, and ground.
The power unit can deliver AC power ranging from 85 to 264V
steplessly without switching to meet varied power requirements.
Plug-in type for better maintainability
Drop-proof terminal screws for ease and safety of installation
Fuse installed in the power line as standard.
Specifications
Input Resistance
Voltage input:
1M
Ω
min. with or without power.
Current input:
4 to 20mA DC: 250
Ω
(standard)
2 to 10mA DC: 250
Ω
1 to 5mA DC: 100
Ω
0 to 20mA DC: 250
Ω
10 to 50mA DC: 10
Ω
Allowable Input
Voltage
Voltage input: 30V DC max., continuous.
(Standard for a span up to 10V)
Current input: 40mA DC max., continuous.
(Standard for 4 to 20mA)
Allowable Output
Load
Voltage output:
1V span and up: 2mA max.
10mV: 10k
Ω
min.
100mV: 100k
Ω
min.
Current output:
Single current output:
750
Ω
max. (for 4-20mA output)
Dual current output:
Output 1: 550
Ω
max. (for 4-20mA output)
Output 2: 350
Ω
max. (for 4-20mA output)
Zero Adjustment
Approx. ±5% of span.
(Adjustable by the front-accessible trimmer.)
Span Adjustment
Approx. ±5% of span.
(Adjustable by the front-accessible trimmer.)
Accuracy Rating Better than ±0.1% of span (at 25°C±5°C)
Temperature
Effect
Better than ±0.2% of span per 10°C change in
ambient.
Selection
Sensitivity
Better than 0.5% of span.
Response Time 85ms max. (0-90%) with a step input at 100%.
Insulation
Resistance
100M
Ω
min. (@ 500V DC) between input,
output 1, output 2, power, and ground.
Dielectric
Strength
Input / [Output 1, Output 2] / [Power, Ground]:
2000V AC for 1 minute (Cutoff current: 0.5mA)
Power / Ground: 2000V AC for 1 minute (Cutoff
current: 5mA)
Output 1 / Output 2: 500V AC for 1 minute
(Cutoff current: 0.5mA)
Surge Withstand
Capability
Tested as per ANSI/IEEE C37.90.1-1989.
Storage
Temperature
-10 to 60°C
Installation Position
Typical Installation Example