9

S8AS

Functions

Functions

Tripping Functions

Note: Three abnormal current tripping types with different tripping current characteristics are supported: standard detection, instantaneous

detection, and extended detection. Select the required tripping type.

*1. Outputs are cut off using semiconductor relays and electrical insulation is not provided.

*2. With the default settings, the alarm display and alarm output can be cleared using one of the following methods.

• Clear using the reset operation.

• Clear by turning the supply power OFF and ON again.

*3. The voltage detection is performed on the voltage after AC/DC conversion in the internal circuits. The displayed voltage will be somewhat

different from the value at the output terminals of the power source due to internal voltage drop. To confirm correct output voltages, measure

the voltages at the branch output terminals.

Alarm

Alarm output

Output status

Alarm display

Abnormal voltage tripping

TRP output: OFF (normally ON)

All branch outputs cut off.

A10

Abnormal current tripping

TRP output: OFF (normally ON)

Relevant branch output cut off.

A11

Abnormal total current tripping (240-W models only)

TRP output: OFF (normally ON)

All branch outputs cut off.

A12

Undervoltage detection

LOW output: OFF (normally ON)

ON

A21

Maintenance forecast monitor

LFE output: OFF (normally ON)

ON

A23

Overheating alarm

LFE output: OFF (normally ON)

ON

A23/HOT

Over-temperature

TMP output: OFF (normally ON)

ON

A30

Function

Operation

Abnormal

voltage tripping

Refer to Chart 1.

*1, *2, *3

The output voltage is monitored and all branch outputs are cut off if the detection voltage is reached. Notification of the status

is provided using the alarm display and the tripping alarm output (TRP).

The alarm display will alternate between the voltage and the alarm code (A10).

Detection voltage: 28.8 V (fixed)

Abnormal

current tripping

Refer to Chart 2.

*1, *2

The output current is monitored and the branch output that is abnormal is cut off if the preset current is reached.

Notification of the status is provided using the alarm display and the tripping alarm output (TRP).

The alarm display will alternate between the current and the alarm code (A11).

Setting range: 0.5 to 3.8 A (in 0.1-A increments). The S8AS-24006N and S8AS-48008N are set to 3.8 A. (Cannot be changed.)

One of the following three abnormal current tripping types can be set. With the S8AS-24006N/48008N, only the standard

detection is supported.

Standard Detection: Tripping within 100 ms. (Abnormal current will be detected and the output will be cut off within 20 ms if

current continuously exceeds the set value for more than 80 ms.)

Instantaneous Detection: Tripping within 20 ms. (Abnormal current will be detected and the output will be cut off within 10 ms

if current continuously exceeds the set value for more than 10 ms.)

Extended Detection: Tripping within 1,000 ms. (Abnormal current will be detected and the output will be cut off within 20 ms

if current continuously exceeds the set value for more than 980 ms.)

Abnormal total

current tripping

*1, *2

Using the abnormal total current tripping function, the S8AS monitors the total output current and when the total output current

exceeds the set value, all branch outputs are cut off. Notification of the status is provided using the alarm display and the

tripping alarm output (TRP). The error code A12 will be shown on the display. There are a number of conditions for the tripping

current and time. If even one of these conditions is detected, the abnormal total current tripping function will be activated.

240 W: Branch outputs are cut off when the total output current is more than 17 A for 2 s, 15 A for 5 s, 13 A for 10 s, or 12 A

for 20 s.

480 W: Branch outputs are cut off when the total output current is more than 27 A for 1 s, 25 A for 2 s, or 22.5 A for 5 s.

External tripping

input

*1

The output can be cut off by inputting a voltage to the external tripping input (TRG terminal). If a shutdown sequence has been

set, outputs will be cut off according to the shutdown sequence.

Each branch output can be enabled or disabled individually. On the S8AS-24006N/S8AS-48008N, all branch outputs are

enabled. (Cannot be changed.)

External input signal width: 10 ms min.

Input signal levels

High level: 19.2 to 30 VDC

Low level: 0 to 2.5 VDC

Tripping can also be performed by using communications (S8AS-24006R/S8AS-48008R only).

Refer to the S8AS User's Manual (Cat. No. Z269) for information on tripping using communications.