Model EA91A＆EA90A
3
WARNING
WARNING
WARNING
1.3.1 Limitation of Installation Location
The electrical device with the intrinsically safe explosion-protected construction consists of the combination
of the intrinsic safety device (EA90A Electro-pneumatic Valve Positioner) to be installed in hazardous area
and the safety barrier (intrinsic safety related device) to be installed in non-hazardous area.
The EA90A Valve Positioner can be installed in hazardous area according to the available explosive gas of
the intrinsic safety device. However, do not install the safety barrier to be electrically connected to the
EA90A Valve Positioner in hazardous area unless the safety barrier is used in combination with other
explosion-protected construction (flameproof explosion-protected construction, etc.)
1.3.2 Combination with Safety Barrier
The safety barrier that does not individually pass the model test in compliance with the Technical Criteria
should not be used by connecting to this electric-pneumatic valve positioner EA90A.
The explosion-protected device type of the safety barrier shall be "ⅡC" and the classification shall be "ia".
Be sure to comply with the conditions since there are limitations of inductance and capacitance for safety
rate and external wiring. (Refer to Item 2.6.2 "Model EA90A Electro-pneumatic Valve Positioner (Intrinsic Safety
Type)" in this manual for maintenance of the EA90A Electro-pneumatic Valve Positioner.)
1.3.3 Maintenance
Consult with Motoyama for maintenance of the EA90A Electro-pneumatic Valve Positioner in principle.
If performing maintenance by user, read the following instructions herein and carefully follow the instructions
described in Chapter 8 "MAINTENANCE" for specific procedures.
(1) Maintenance of EA90A Valve Positioner
When performing maintenance the EA90A Valve Positioner installed in hazardous area, carefully make sure
before and during maintenance whether the explosive gases are absent or not by using gas detector.
(2) Maintenance during Operation
Do not perform maintenance of the EA90A Valve Positioner while the power is being turned ON.
When performing maintenance with the valve positioner turned ON due to circumstances, maintenance must
be limited to visual inspection and adjustment of movable parts such as zero adjustment and stroke
adjustment.
(3) Repairs
a ) Turn OFF the power, disconnect the external wiring, and then move the EA90A Valve Positioner to non
-hazardous area.
b ) Both mechanical and electric repairs are restricted to only restoring the valve positioner to its
original condition in principle.
c ) The repair by user shall be limited to repair using general tools without soldering iron.
(4) Verification of Intrinsic Safety
Check the following items in non-hazardous area when confirming intrinsic safety of the EA90A Valve
Positioner at periodic maintenance of the EA90A Valve Positioner and at replacement of the parts for
repairs.
Check the insulation performance by applying voltage with 500V for one minute to the plus (+)
terminal or the minus (‒) terminal, and the grounding terminal of the terminal block.
1.3 Safety Instructions on Model EA90A Electro-pneumatic Valve Positioner
The EA90A Electro-pneumatic Valve Positioner (intrinsically safe explosion-protected construction) consists of
one intrinsic safety device (electro-pneumatic valve positioner) designed and produced following to the new
Technical Criteria and one intrinsic safety related device (safety barrier).
Use the safety barrier individually passed the device test for combining with the EA90A Electro-pneumatic
Valve Positioner. Select the safety barrier that complies with the combination conditions described in Item 2.6.2
"Model EA90A Electro-pneumatic Valve Positioner (Intrinsic Safety Type) in this manual.
CAUTION
CAUTION
CAUTION
