
CHV-2 INSTALLATION INSTRUCTIONS – REVISION R (2020)
DO NOT MOVE the BATTERY JUMPER from “OFF” to “ON” position UNTIL STEP 6 BELOW. FAILURE TO OBSERVE THIS
PRECAUTION WILL RESULT IN SIGNIFICANT DISCHARGE OF THE BATTERIES AND REDUCED BATTERY LIFE. THE CHV-2
OPERATES FROM EXTERNAL POWER THAT MUST ALWAYS BE “ON” EXCEPT DURING A POWER FAILURE. IF EXTERNAL
POWER IS SWITCHED OFF FOR AN EXTENDED PERIOD, THE BATTERIES WILL RUN DOWN AND THE UNIT WILL TRIGGER.
1) Mount the CHV-2 in its case to a load-bearing wall, ceiling, floor, stud or joist with at least two screws through the case mounting
flanges. Any convenient mounting attitude is acceptable. (The CHV-2 will automatically orient itself.) The location chosen must be
relatively free from man-made or machine-made vibration. (Excessive vibration will cause false triggering and reduced battery life.)
2) Remove the transparent case cover by loosening the four (4) captive screws until the cover comes free. All wiring to the CHV-2
passes through the conduit hole near the terminal strip.
3) Connect the OUTPUT terminals to the elevator control system. The output is an isolated Form C contact so that systems requiring
a contact closure (NO) or break (NC) to the COMmon terminal can be used. NO means that the path from COMmon to NO is OPEN
until a triggering event occurs. NC means that the path from COMmon to NC is CLOSED until a triggering event occurs.
4) Wire the main (“ALWAYS ON”) power (AC or DC or both) to the unit:
a) AC main voltages of 80 to 135 VAC (terminals P1 to P2) or 160 to 270 VAC (terminals P1 to P3) may be used. The unit can
operate on either 50 or 60 Hz current. An earth ground (“green wire”) terminal is provided in the case.
b) DC main voltage of 12 to 32 VDC may be used by connecting to the (+) and (-) terminals. Be sure to observe proper
polarity. There is a reverse-polarity protection diode in the CHV-2; if the unit is connected incorrectly, it won't function.
c) BOTH AC and DC may simultaneously be connected to the unit. In this case the DC input can serve as a backup voltage
supply. The priorities of main voltage source used by the CHV-2 are (1)AC, (2)external DC, (3)internal battery.
5) Set the sensitivity jumper in accordance with instructions overleaf.
6) NOW move the BATTERY jumper from its OFF position to its ON position (located at J3 on the circuit board).
7) SAFETY WARNING: Replace the transparent case cover. UL requirement: The cover, with pushbutton standoffs mounted, shall be
in place at all times when AC line voltage is applied to the unit.
8) Apply main power (AC or DC or both) to the unit. The unit will fail its power-up self test and trigger. The red TRIGGER LED will light
up and the latching relay will click. The MAIN POWER LED (Yellow) should illuminate. If it does not, check the main power source(s)
and wiring.
9) Press the RESET button. The TRIGGER LED should go off (and stay off). The CHV-2 will perform its initial power-up self test. The
TEST/STATUS LED coming on for approximately one second and then turning off visually indicates this. The REPLACE BATTERY LED
coming on for approximately one second and then turning off follows this. This repeats (twice). Shortly after this sequence, the
CHV-2 begins its normal monitoring function. The unit should NOT trigger unless an earthquake event occurs.
In external AC or DC powered operation, it is normal for the TEST/STATUS and REPLACE BATTERY LEDs to come on for one second
every 10 minutes as the unit performs its automatic self tests. In addition, the REPLACE BATTERY LED may remain on (flashing if it is
time to replace the batteries), and the MAIN POWER LED will be lit. However, in battery-powered mode, no LEDs should be on. If the
TEST/STATUS LED comes on and the unit is NOT triggering, the CHV-2 is mounted in a location with too much man-made vibration.
This will cause the unit to be constantly "awakened" from its low-power stand-by mode and will prematurely run down the
batteries. If this occurs, select another location for the unit that is free from excessive vibration or set the trigger level jumper to a
lower sensitivity.