Description Of The Circuit Board - GE Hydran 201 i Instruction Manual

Chapter 3 • Hydran 201Ci Controllers
2. Door-Mounted Alarm Indicators and Push-buttons: The two illuminated push-
buttons are mounted on the cabinet door of the instrument. Each local indicator
latches on when the corresponding gas alarm relay is energized. The indicator
remains on when the alarm relay turns off and it must be cleared (or "acknowledged")
by pressing the illuminated indicator. The indicator clears only when the corre-
sponding gas alarm relay has de-energized.
3. Enclosure: The H201Ci-1 cabinet is rated Type NEMA 4X. With the standard
internal heater, the instrument operating temperature ranges from -40 to +55 °C (-40
to +131 °F).
An internal view of the H201Ci-1 is presented in Figure 3-6 on page 3-11.
4. Digital Display Circuit Board Cover: This cover protects the display circuit board,
which includes the digital voltmeter and the connections of the two push-buttons.
5. Electronic Circuit Board: The circuit board incorporates all the electronic functions
of the H201Ci-1: H201Ti TDM pulse decoder, alarm relay drivers, configurable
analog output amplifiers, display signal conditioning, supervisory link supply,
communication ports and modem (optional) management, enclosure heater control,
and ac supply voltage selector. See Section C.3 on page C-3 for a simplified block
diagram of the circuit.
6. Main Terminal Block: The ac power supply, the analog output, the three alarm relays
(Alarm 1 = Gas High, Alarm 2 = Gas High-High, and System OK), the supervisory
link cables and the RS-485 LAN are connected to this 40-screw terminal block. For
wiring details, see Table D-11 on page D-8.
ELECTRICAL SHOCK HAZARD. Voltage of 115 or 230 Vac is
WARNING
CAUTION
present on several connecting screws of this terminal block.
3.2.3

Description of the Circuit Board

The circuit board of the Hydran 201Ci-1 is presented in Figure 3-7 on page 3-12.
7. RS-232 Computer Port Connector, DB-9 Male (J10): This standard connector is used
to interface the H201Ci-1 directly to a PC or to a smart modem. For wiring details,
see Table D-13 on page D-11. The J16 USB computer port (item 8 in Figure 3-7 on
page 3-12) is also available.
3-10 Rev. 6, March 2011 Part 17997