MTT MS3708 User Manual Download Page 2

  User's Manual 

MS3708 

Slim Plug-In Frequency/Analog Converter with Isolated Single/Dual Output 

 

Rev. 1.40 

 
 

 

 
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 Measurements: 

  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.) 

 

4. About the Product

 

The MS3708 converts pulse train signals into isolated DC signals.

 

 

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 power 

30k

Ω

 min. without power 

Current input: 250

Ω

 (standard for 4-20mA) 

 

Allowable Input 
Voltage 

DC voltage input: 30V DC max., continuous. 
DC current input: 40mA DC max., continuous. 
AC voltage input: 200Vp-p AC max., 
continuous (up to ±100V with reference to 0V). 

 

Input Pulse 
Width 

4µs min. 

 

Duty Ratio 

40 to 60% 

 

Allowable Output 
Load 

Voltage output: 

1V span and up: 2mA max. 
10mV: 10k

 min. 

100mV: 100k

 min. 

 

Current output: 

Single current output: 

750

 max. (for 4-20mA output) 

Dual current output: 

Output 1: 550

 max. (for 4-20mA output) 

Output 2: 350

 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 ±0.3% of span 
Ripple: 0.2%p-p or less of span (for at least 
10% input) (at 25°C±5°C) 

 

Temperature 
Effect 

Better than ±0.2% of span per 10°C change in 
ambient. 

 

Response Time 

Input Frequency 

0-90% with a step input 

at 100% 

 

20Hz 8s 

max. 

200Hz 1s 

max. 

2kHz 500ms 

max. 

20kHz 500ms 

max. 

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

 

Reviews: