MODEL: MDHA

http://www.m-system.co.jp/

MDHA SPECIFICATIONS

ES-8166 Rev.2 Page 1/3

Lightning Surge Protectors for

Electronics Equipment M-RESTER

LIGHTNING SURGE PROTECTOR

FOR POWER SUPPLY USE

(DC power use; life monitor)

Functions & Features

•Designed specifically for DC power supplies up to 5 amps

•Life monitor function helps you to decide when you should

replace the M-RESTER; reduces maintenance and prevents

downtime

•LED display and alarm contact output indicate the

degradation and life span of the surge protection circuits

•No power supply interruption even when the unit is

degraded or at the end of its life

50

(1.97)

123

(4.84)

80

(3.15)

mm (inch)

DEL: MDHA–[1]

ORDERING INFORMATION

• Code number: MDHA-[1]

Specify a code from below for [1]

(e.g. MDHA-24)

[1] OPERATIONAL VOLTAGE

12: 12 V DC

24: 24 V DC

GENERAL SPECIFICATIONS

Construction: Plug-in

Connection: M3.5 screw terminals (torque 0.8 N·m)

Screw terminal: Chromated steel

Housing material: Flame-resistant resin (black)

Alarm indicators

Power: The green LED turns on while the circuit is alive and

the internal fuse on the voltage limiter side is not blown;

and is off when the power supply is removed or this fuse is

blown.

Alarm: Tricolor LED (green/amber/red)

•Remains off when the power supply is first turned on.

•Green: The unit has received one or more surges.

•Amber: Replacement is recommended.

•Red: The life span has ended.

Alarm contact

The N.C. contact is on when the life span of the discharge

elements has ended, when the voltage limiter has

degraded, when the fuses are blown, and/or when the

power supply is removed.

Rating: 125 V AC @ 0.5 A (cos ø = 1)

30 V DC @ 1 A (resistive load)

Maximum switching voltage: 125 V AC or 110 V DC

Maximum switching power: 62.5 VA or 30 W

Minimum load: 5 V DC @ 1 mA

Life status table

POWER ALARM

ALARM

STATUS

REPLACEMENT

LED

LED

CONTACT

OFF

Normal

(no surge)

No Need

ON

Green

OFF

Normal

(multiple hits)

Amber

Near End

Without Delay

Red

ON

End (degraded)

Now

Power supply

Now if the

OFF

----

----

removed or

power supply

End (degraded)

is normal.

INSTALLATION

Operating temperature: -5 to +55°C (23 to 131°F)

Operating humidity: 30 to 90 %RH (non-condensing)

Mounting: Surface or DIN rail

Weight: 500 g (1.1 lbs)

PERFORMANCE

Operational line voltage:

10.8 – 13.2V DC (MDHA-12)

21.6 – 26.4V DC (MDHA-24)

Discharge voltage (peak voltage)

• Line to line:

±15 V min. (MDHA-12)

±30 V min. (MDHA-24)

• Line to ground: ±160 V min.

Max. surge voltage (Up)

• Line to line:

±80 V max. (MDHA-12)

±120 V max. (MDHA-24)

• Line to ground: ±700 V max.

(This is the maximum voltage that could pass through M-

RESTER. Protected equipment must be able to withstand

this voltage for a very short time period.)

Response time:

• Line to line: ≤ 4 nsec.

• Line to ground: ≤ 20 nsec.

Leakage current