·Some details are not shown. Please refer to specification sheets for all information.

MDJST

Lightning Surge Protectors for
Electronics Equipment M-RESTER

LIGHTNING SURGE PROTECTOR FOR
STANDARD SIGNAL LINE
(fast response: 3 nsec.)

Functions & Features
• Designed specifically for 4 – 20 mA DC and pulse signal line
• Battery-powered status indicator
• High discharge current capacity 20 kA (8/20 μs)
• Shield terminal provided
• Compatible with IEC 61643-21 categories C1, C2, D1.

MODEL: MDJST–[1][2]

ORDERING INFORMATION
• Code number: MDJST-[1][2]
 Specify a code from below for each [1] and [2].
(e.g. MDJST-24Y)

[1] NOMINAL VOLTAGE
12: 12 V DC
24: 24 V DC
48: 48 V DC

[2] STATUS INDICATOR
A1: Monitor LED
A2: Monitor LED and alarm output
Y: None

GENERAL SPECIFICATIONS
Construction: Plug-in
Surge protection type: Surge energy limiting type
Connection: M3.5 screw terminals (torque 0.8 N·m)
Screw terminal: Nickel-plated steel
Housing material: Flame-resistant resin (black)
Status indicator
  Monitor LED
: Green, activated by Check button
  ON in normal operating
  OFF in degradation of the voltage limiter or battery
  discharged
Degradation judged: When the leakage current at the voltage limiter exceeds approx. 50 μA. 1 V or more is necessary for the signal (line to line) voltage.
Check button: Push button; momentary
Alarm output: Open collector
  28 V DC @ 100 mA (resistive load)
  OFF in normal conditions
  ON in degradation of the voltage limiter or
  battery discharged
  Saturation voltage 3.5 V DC
Battery: Lithium; No recharge or replacement available.
Battery life: 10 years (when used ≤ 2 minutes/month)

INSTALLATION
Operating temperature: -5 to +55°C (23 to 131°F)
Operating humidity: 30 to 90 %RH (non-condensing)
Mounting: Surface or DIN rail; Standard Rack Mounting Frame BX-16H available
Weight: 230 g. (0.51 lb)

PERFORMANCE
Insulation resistance: ≥ 100 MΩ with 250 V DC (Line to alarm output)
(The voltage more than 250 V DC turns the discharge element on; then the insulation between lines and alarm output will be lost)
Surge protection: IEC 61643-21 Categories C1, C2, D1

EXTERNAL VIEW

EXTERNAL DIMENSIONS & TERMINAL ASSIGNMENTS unit: mm (inch)

SCHEMATIC CIRCUITRY & CONNECTION DIAGRAM

M-System Co., Ltd.