DHI External Reservoir for PPCH User Manual

EXTERNAL RESERVOIR, P/N 402102,
INCLUDES:

DESCRIPTION QTY PART NO.

Assembly, External Reservoir kit 1 402167

Tubing, PFA, 1/4 in. O.D. x 300 cm 1 101450-Z

Adaptor, 1/8 in. NPTM x 1/4 in. Swage 1 101532

Nut, SS, 1/4 in. Swage 1 100247

Ferrule, SS, front, 1/4 in. Swage 1 100248

Ferrule, SS, rear, 1/4 in. Swage 1 100249

INTRODUCTION

The External Reservoir kit is designed for use with the
PPCH Hydraulic Pressure Controller. The external
reservoir is provided for applications requiring more
fluid than can be held in the 300 cm
The external reservoir is connected in series with the
internal reservoir so that internal reservoir features are
still available.

3

internal reservoir.

External Reservoir

for PPCH™

4 liter capacity

P/N 402102

Instruction Sheet

NOTE: This instruction sheet is provided as a

quick installation guide. For further details, see
the PPCH Operation & Maintenance Manual’s
sections on use of an external reservoir.

INITIAL CONSIDERATIONS FOR
INSTALLATION OF RESERVOIR

1. Internal reservoir attachments not used: When
using the internal reservoir, a fill tube bracket,
sight tube and funnel are mounted on the rear of
the PPCH. These attachments are not used with
the external reservoir. If the attachments are
already installed, remove them. Be sure to close
the FILL/DRAIN valve prior to removal.

2. Reservoir above the PPCH: The bottom of the
reservoir must be higher than the PPCH
instrument to ensure a proper gravity feed of fluid
to the internal reservoir and pump. Avoid low
points in the tubing between PPCH and the
reservoir.

Figure 1. External Reservoir

1. Return port, 1/4 in.
Swage

2. Supply port, 1/4 in.
Swage

3. Mounting bracket 6. Return Tube

4. Fill cap, 1/2 in. Swage

5. Vent Plug, 10-32 x 1/8

3. Secure the reservoir: Pass throughs (5.4 mm Ø)
are provided in the mounting bracket for securing
the reservoir.

4. Prepare the tubes: 300 cm of 1/4 in. O.D. PFA
tubing is provided for making tube connections
between the external reservoir and the PPCH.
The fittings on the external reservoir are 1/4 in.
Swage. The ferrules need to be swaged to each
end of the tubes.

5. Adaptor for Reservoir return: Use the supplied
1/8 in. NPTM x 1/4 in. Swage adaptor for the
EXTERNAL RESERVOIR RETURN bulkhead on
the PPCH.

To prevent accidental draining of the internal

reservoir, keep the FILL/DRAIN valve in the closed
position until the external reservoir is connected.

INSTALLATION OF RESERVOIR

Close valve: Close the reservoir FILL/DRAIN valve.

Install adaptor: Install the 1/8 in. NPTM x 1/4 in.

Swage adaptor in the PPCH EXTERNAL
RESERVOIR RETURN bulkhead fitting.

Connect tubes: Connect a tube from the PPCH

EXTERNAL RESERVOIR RETURN port, to the

return port (1) on the external reservoir.

Connect tubes: Connect a tube from the PPCH

FILL/DRAIN port to the supply port (2) on the

external reservoir. The stainless steel Swage fittings
are used at the PPCH FILL/DRAIN port connection.

Fill external reservoir: Fill the external reservoir

through the 1/2 in. Swage brass fitting (4) with the
same fluid as is used in the PPCH. Do not fill past
the top of the stainless steel return tube.

The MAX FILL label on the rear of the PPCH does

not apply when using an external reservoir.

The top of the return tube defines the fluid head

applied to the PPCH’s Q-RPT when in a VENT
condition.

Enable reservoir return: Turn the PPCH

RESERVOIR RETURN valve to the EXTERNAL

position, and loosen the vent plug on top of the
Reservoir – this is a 10-32 x 1/8 threaded plug.

Be sure the external reservoir is open to

atmosphere so proper system venting and
zeroing can occur.

Purge overflow circuit: Purge air from the

internal reservoir and the overflow circuit:

• Prepare the 1/8 in. NPT plug (that was

previously used in the external reservoir return
bulkhead) for use in the OVERFLOW
bulkhead fitting by wrapping the NPT threads
with Teflon tape.

• Slowly turn the FILL/DRAIN valve to the

OPEN position.

• Plug the OVERFLOW bulkhead port when

gas-free oil begins to flow out.

Fill the reservoir return tube: Finish the purge

process by running the [PRIME] function on the
PPCH to cycle fluid from the reservoir supply,
through the PPCH, and back out to the External
Return tube. First ensure the TEST port is plugged.

When the PPCH is vented, the system connected

to the TEST port is also connected to the
External Reservoir (which is higher than the TEST
port). If there is an open point in the system
below the fluid level in the reservoir, fluid will run
out of the system at this open point.

Document 560072 050412

DH Instruments, Inc.

4765 East Beautiful Lane
Phoenix AZ 85044-5318
USA

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