Mitsubishi Electric CITY MULTI PUHY-400YMF-B Service Handbook page 137

2 LEV2
Pulse Signal Output and Valve Operation
Output (Phase) Output State
No. 1 2
ø1 ON OFF OFF ON
ø2 ON ON OFF OFF
OFF ON
ø3
ø4 OFF OFF ON
LEV Valve Closing and Valve Opening Operations
Valve Closing
A
E
B
Increased choke range
(80 ~ 100 pulses)
3 4
ON OFF
ON
D
C
Valve Opening
Full Open
2000 pulses
Pulse Count
Output pulses change in the following orders when the
Valve is Closed
Valve is Open
*1. When the LEV opening does not change, all output
phases are OFF.
2. When the output opens a phase and stays ON, the
motor will not run smoothly and will clack and
vibrate.
3. When the power source is turned on, a close valve
signal (2200 pulse) is sent to confirm the valve
position, ensuring a starting point of A.
4. When the valve is operating smoothly, there will be
no sound or vibrations from the LEV, when opera-
tion goes from point E to point A, the valve locks
and open phases create a considerable noise.
5. The noise emanates from the driver and can be
easily discerned by placing a screwdriver against it
and then placing your ear against the handle.
–134–
1 → 2 → 3 → 4 → 1
4 → 3 → 2 → 1 → 4