© 2016 Littelfuse Protection Relays & Controls

Time Delay Relays

Dedicated - Interval

www.littelfuse.com/thd2

Rev: 1-A-061016

External Resistance vs.Time Delay

This chart applies to externally adjustable part numbers.

The time delay is adjustable over the time delay range selected by varying

the resistance across the RT terminals; as the resistance increases the tie

delay increases.

When selecting an external RT, add the tolerances of the timer and the RT

for the full time range adjustment.

Examples: 1 to 50 S adjustable time delay, select time delay range 1 and

a 50 K ohn RT. For 1 to 100 S use a 100 K ohm RT.

Function Diagram

INTERVAL (IMPULSE-ON)

V = Voltage

NO = Normally

Open Contact

NC = Normally

Closed Contact

TD =Time Delay

R = Reset

= Undefined

Time

THD2 SERIES

Specifications

Time Delay

Range

0.1s - 1000m in 6 adjustable ranges or fixed

Repeat Accuracy

±0.5% or 20ms, whichever is greater

Tolerance

(Factory Calibration)

≤ ±1%

Reset Time

≤ 150ms

Time Delay vs Temp.

& Voltage

≤ ±2%

Input

Voltage

24, 120, or 230VAC

Tolerance

±20%

AC Line Frequency

50/60 Hz

Output

Type

Solid state

Form

NO, closed during timing

Maximum Load Current

Output

Steady State

Inrush**

A

6A

60A

B

10A

100A

C

20A

200A

Minimum Load Current

100mA

Voltage Drop

≅

2.5V at rated current

OFF State Leakage Current

≅

5mA @ 230VAC

Protection

Circuitry

Encapsulated

Dielectric Breakdown

≥ 2000V RMS terminals to mounting surface

Insulation Resistance

≥ 100 MΩ

Mechanical

Mounting **

Surface mount with one #10 (M5 x 0.8) screw

Dimensions

H 50.8 mm (2”); W 50.8 mm (2”);

D 38.4 mm (1.51”)

Termination

0.25 in. (6.35 mm) male quick connect terminals

Environmental

Operating/Storage

Temperature

-40° to 60°C / -40° to 85°C

Humidity

95% relative, non-condensing

Weight

≅

3.9 oz (111 g)

**Must be bolted to a metal surface using the included heat sink compound. The maximum

mounting surface temperature is 90°C. Inrush: Non-repetitive for 16ms.