Hach 900 Auxiliary Connection, V dc Connector Pin Assignments, Auxiliary Pin Assignments

Section 3

•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).

3.9 12 V dc

This connection is for supplying power to the sampler controller electronics. Power is normally supplied to the sampler controller electronics from either a battery or a power supply located in the pocket directly behind the sampler controller housing.

In the event of a power outage, an optional 12 V dc battery backup is available (Cat. No. 1803). This power backup maintains power to the sampler when ac power fails.

Table 1 12 V dc Connector Pin Assignments

Pin

A

B

Signal Description

ground

12 to 17 V dc unregulated

3.10 Auxiliary Connection

The auxiliary interface connector is a general purpose input/output port. Each signal is described in Table 2.

Table 2 Auxiliary Pin Assignments

Pin	Signal Description	Wire Color	Purpose	Rating
A	12 V dc	White	This pin can be used to power an external device or flow meter. Must
			be used in conjunction with Pin B (ground).	13.8 V dc
B	ground	Blue	Connected to dc ground and is isolated from the earth ground found	nominal
			in the ac power line.
			With the sampler is 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	5 to 17 V dc
			sampler is capable of accumulating from 1 to 9999 input pulses.	pulse with
C	Flow Pulse Input	Yellow	The 12 V dc line found on Pin A can be used directly with a simple	duration of
			contact closure to Pin C or an external 5 to 12 V dc pulse may be	at least
			applied providing the ground side of the external signal is connected	25 ms.
			to the sampler ground at Pin B. This count is actuated at the
			beginning of the input signal (the leading edge of the pulse).

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8544install.fm	12 V dc