ES-8176-B Rev.10

MH-205A

Lightning Surge Protectors for
Electronics Equipment M-RESTER

LIGHTNING SURGE PROTECTOR FOR POWER SUPPLY USE

(5 A, 200 / 220 / 240 V AC)
Functions & Features
• Designed specifically for power requirements of medium capacities
• Protecting electronic equipment from lightning surges that enter through substations and step-down transformers
• Discharge element failure triggers the fuse blown and alarm contact closed
• Also effective in rejecting switching transients generated by thyristors, circuit breakers, motor starters, etc.
Typical Applications
• Control panels
• Telemetering systems

MODEL: MH–205A

ORDERING INFORMATION

• Code number: MH-205A

GENERAL SPECIFICATIONS

Connection: M4 screw terminals (torque 1.6 N·m)
Screw terminal: Nickel-plated brass
Housing material: Steel plate t = 1.6 (black)
Alarm indicator: Discharge element failure indicator turns white when the fuse is blown.
Monitor lamp: Red neon lamp turns on when the power is supplied.
Alarm relay contact: Turns ON with discharge element failure (when the fuse is blown)
•Rated load: 100 V AC @ 250 mA (cos ø = 1)
100 V DC @ 250 mA (resistive load)
•Maximum switching voltage: 125 V AC or 125 V DC
•Maximum switching power: 25 VA or 25 W
•Minimum load: 5 V DC @ 10 mA

INSTALLATION

Operating temperature: -5 to +55°C (23 to 131°F)
Operating humidity: 30 to 90 %RH (non-condensing)
Mounting: Surface
Weight: 3.0 kg (6.6 lb)

PERFORMANCE

Discharge voltage (peak voltage)
Line to line: 410 V min.
Line to ground: 410 V min.
Maximum surge voltage
Line to line: 700 V max.
Line to ground: 700 V max.
(The maximum voltage that could pass through M-RESTER. Protected equipment must be able to withstand this voltage for very short time period.)
Response time: ≤ 0.1 μsec.
Leakage current
Line to line: ≤ 1 mA at 300 V DC
Line to ground: ≤ 1 mA at 300 V DC
Discharge current capacity: 10000 A (8/ 20 μsec.)
Maximum load current: 5 A
Voltage drop: ≤ 2 V (50/60 Hz)
Rated line voltage: 200 V / 220 V / 240 V AC

CONNECTION EXAMPLES

GROUNDING

EXTERNAL DIMENSIONS & TERMINAL ASSIGNMENT unit: mm [inch]

MOUNTING REQUIREMENTS unit: mm [inch]