Hach 900 MAX ユーザーズマニュアル

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Auxiliary Receptacle Pin Identification
8990hrd.fm
Section 2
Important: Whenever electricity is present, there is a possibility of electrical 
shock. Before connecting the sampler to an ac power source, the following 
safety precautions should be taken:
Check the power source to make sure that it satisfies the ac power 
requirements of the sampler.
Make sure that all electrical installations and connections are in 
accordance with national and local electrical codes.
Before performing any maintenance, disconnect the sampler from the 
power source.
Do not attempt to make any connection or otherwise handle the electrical 
components of the sampler when connected to ac line power if the 
immediate area is wet, or if hands or clothing are wet.
If the circuit breaker or fuse in the ac power source is tripped, determine 
the cause before restoring power to the sampler.
Make sure the power circuit is grounded and protected with a Ground 
Fault Interrupter (GFI).
2.9 Auxiliary Receptacle Pin Identification
Pin A/White (12 V dc)
Powers an external device or flow meter. Must be used in conjunction with Pin B (ground).
Pin B/Blue (Ground) 
Connected to dc ground and is isolated from the earth ground found in the ac power line.
Pin C/Yellow (Pulse Input)
With the sampler in Flow Proportional mode and connected to an external flow meter, a 5 to 
12 V dc input pulse lasting at least 25 milliseconds will cause the sampler to decrement one 
count. The 12 V dc line found on Pin A can be used directly with a simple contact closure to 
Pin C or an external 5 to 12 V dc pulse may be applied providing the ground side of the 
external signal is connected to the sampler ground at Pin B. This count is actuated at the 
beginning of the input signal (the leading edge of the pulse).
Pin D/Black 
(Liquid Level Actuator/ 
Auxiliary Control Input)
This line is held at 5 V dc inside the sampler. When shorted to ground (Pin B), a signal is sent 
to the microprocessor inside the sampler causing it to “wake up” and begin or resume its 
sampling program. It can be used in conjunction with a simple level float to actuate the 
sampler when liquid is present or to take over after a second sampler has finished its 
program. It may also be used with any device (such as a pH meter) that produces a dry 
contact output to control the sampler in response to some user-defined condition (i.e. high or 
low pH); must be used in conjunction with Pin B.
Pin E/Red (Special Output)
Normally at 0 V dc, this line goes to 12 V dc upon any of the selected events described in. 
Pin F/Green 
(Program Complete Output)
Normally an open circuit, this line switches to ground for 90 seconds at the conclusion of the 
sampling program. Used to “wake up” another sampler to take over sampling or to signal an 
operator or data logger upon the completion of the sampling program. This pin is also used to 
signal the bottle full condition in a single bottle/continuous mode, and will transmit the bottle # 
to an 950 Flow Meter if the program complete signal is disabled.