MODEL: JB2

JB2 SPECIFICATIONS

ES-2642 Rev.5 Page 3/5

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

to the same value as the CAS control signal, and turns on to

CAS control mode. The response time constant can be

set/changed with the PU-2x.

If the external command contact is closed during the

transition, the JB2 output holds the signal of this moment

and turns on to MAN control mode.

■ JB2 ACTIONS AT POWER RECOVERY

The actions at power recovery can be switched by actions

and settings at the moment of power failure.

a) MAN command status is OFF at recovery.

CAS mode

b) MAN command status is ON at recovery.

• Output value after power on is “FIXED VALUE”.

Manual control starts with fixed output value.

• Output value after power on is “HOLD VALUE”.

Manual control starts with output value at the moment of

power failure.

(Approx. 0.3 second is required to switch from CAS to MAN

when the power supply is recovered. Refer to the

instruction manual.)

■ DIFFERENCE BETWEEN JB AND JB2/A

Means to back up the output value is different.

• JB: STATIC RAM (A large capacitance capacitor holds the

value until the capacitor is discharged.)

until the next rewrite.)

Therefore, the output value at power recovery during “MAN”

control mode is as shown below.

• JB: When recovering within the memory time, JB outputs

the value at the moment of power failure.

When recovering without the memory time, JB outputs the

fixed value.

• JB2/A: The output value at power recovery is selectable,

whether the value at the moment of power failure or the

fixed value.

■ COMPATIBILITY BETWEEN JB2 AND JB2/A

For JB2/A, the operation at power recovery is selectable.

When JB2 (without “/A”) is replaced with JB2/A compatibly,

set JB2/A according to the instruction manual.